Water based anionic polymers for inkjet inks

ABSTRACT

The present invention provides a durable, external surfactant free, anionic, water based jet ink polymer which when formulated into an ink jet ink results in a printing that has an excellent adhesion to metal or plastic substrates. Such a jet ink polymer is suitable performance replacement of solvent soluble polymers currently in commercial use. The hybridized copolymer comprises a hydrophobic functional polymeric backbone comprised of a polysiloxane polymer, a polyolefin polymer, or a functional polyvinyl polymer. The hybridized copolymer also comprises a plurality of copolymeric side chains attached to the backbone, comprising a polymerizable acid-containing unsaturated monomer, and a polymerizable unsaturated monomer. The use of the inks of the present invention enhances performance criteria such as print-head open time, ink stability, and resistance to typical water based cleaners.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. §119(e) to earlier filed U.S. patent application Ser. No. 61/716,004, filed on Oct. 19, 2012, the disclosure of which is incorporated herein by reference in its entirety for all purposes.

FIELD OF INVENTION

The present invention relates to a water based ink jet copolymer, water dispersions for ink jet printing, and water-based inks for ink-jet printing.

BACKGROUND

The ink-jet technology is a contact free dot matrix printing procedure. Ink is issued from a small aperture directly onto a specific position on a medium. Hue P. Le, Journal of Imaging Science and Technology, Volume 42, Number 1, January/February 1998. Inkjet printing is a non-impact method for producing printed images by the deposition of ink droplets in a pixel-by-pixel manner to an image-recording element in response to digital signals. There are various methods that may be utilized to control the deposition of ink droplets on the image-recording element to yield the desired printed image. In one process, known as drop-on-demand inkjet, individual droplets are projected as needed onto the image-recording element to form the desired printed image. Common methods of controlling the ejection of ink droplets in drop-on-demand printing include thermal bubble formation (thermal inkjet (TIJ)) and piezoelectric transducers. Thermal inkjet printers use resistors to create heat, which in turn vaporizes ink to form a bubble; as the bubble expands, some of the ink is pushed out of the nozzle. A vacuum is created when the bubble collapses, which pulls more ink from the cartridge into the print head. In another process known as continuous inkjet (CU), a continuous stream of droplets is generated and expelled in an image-wise manner onto the surface of the image-recording element, while non-imaged droplets are deflected, caught, and recycled to an ink sump. Inkjet printers have found broad applications across markets ranging from desktop document and photographic-quality imaging, to short run printing of grand format, billboard advertisements and lightfast industrial labeling.

Ink compositions containing colorants used in inkjet printers can be classified as either pigment-based, in which the colorant exists as pigment particles suspended in the ink composition, or as dye-based, in which the colorant exists as a fully solvated dye species that consists of one or more dye molecules. Pigments are highly desirable since they are far more resistant to fading than dyes. However, pigment-based inks have a number of drawbacks. Great lengths must be undertaken to reduce a pigment particle to a sufficiently small particle size and to provide sufficient colloidal stability to the particles. Pigment-based inks often require a lengthy milling operation to produce particles in the sub-micron range needed for most modern ink applications. If the pigment particles are too large light scattering can have a detrimental effect on optical density and gloss in the printed image.

Water-based pigment dispersions are well known in the art, and have been used commercially for applying films, such as paints, to various substrates. The pigment dispersion is generally stabilized by either a non-ionic or ionic technique. When using the non-ionic technique, the pigment particles are stabilized by a polymer that has a water-soluble, hydrophilic section that extends into the water and provides entropic or steric stabilization. Representative polymers useful for this purpose include polyvinyl alcohol, cellulosics, ethylene oxide modified phenols, and ethylene oxide/propylene oxide polymers. While the non-ionic technique is not sensitive to pH changes or ionic contamination, it has a major disadvantage for many applications in that the final product is water sensitive. Thus, if used in ink applications or the like, the pigment will tend to smear upon exposure to moisture.

In the ionic technique, the pigment particles are stabilized by a polymer of an ion containing monomer, such as neutralized acrylic, maleic, or vinyl sulfonic acid. The polymer provides stabilization through a charged double layer mechanism whereby ionic repulsion hinders the particles from flocculating. Since the neutralizing component tends to evaporate after application, the polymer then has reduced water solubility and the final product is not water sensitive.

U.S. Pat. No. 5,085,698 discloses a pigmented ink for ink jet printers which comprises an aqueous carrier medium, and pigment particles dispersed in an AB or BAB block copolymer having a hydrophilic segment and a segment that links to the pigment. The A block is a hydrophobic polymer of an acrylic monomer, whereas the B block(s) is a hydrophobic polymer of an acrylic monomer.

Graft copolymeric stabilizers comprising various acrylate derivatives are disclosed in U.S. Pat. No. 6,103,781. The incorporation of organosols having crystallizable polymeric moieties into the ink compositions provided improved blocking resistance and improved erasure resistance when used in ink transfer, ionographic, electrographic and electrophotographic color printing or proofing processes.

SUMMARY OF THE INVENTION

One of the purposes of this invention is to provide a durable, external surfactant free, anionic, water based jet ink polymer which when formulated into an ink jet ink provides printing that has excellent adhesion to metal or plastic substrates. Such jet ink polymer is suitable performance replacement of solvent soluble polymers currently in commercial use. The use of the inks of the present invention enhances performance criteria such as print-head open time, ink stability under varying conditions, and resistance to typical water based cleaners.

One of the aspects of the present invention is a hybridized copolymer comprising

(a) a hydrophobic functional polymeric backbone of an average molecular mass from about 15 to about 200 kilodaltons, wherein the polymeric backbone comprises a polymer selected from the group consisting of a functional polysiloxane polymer, a functional polyolefin polymer, and a functional polyvinyl polymer; and

(b) a plurality of copolymeric side chains attached to the backbone, wherein one or more side chains comprise a reaction product of a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer.

SUMMARY

This hybridized copolymer is a graft copolymer, that may have many uses within the coating and film applications, but it is especially useful as a binder component in ink jet inks. The hybridized copolymer comprises a backbone and a plurality of copolymeric side chains. The backbone is a hydrophobic functional polymeric chain that comprises a functional polysiloxane polymer, a functional polyolefin polymer, a functional polyvinyl polymer, or any copolymer of the three. Particularly suitable polyvinyl polymers are copolymers of vinyl chloride, vinyl acetate and maleic acid.

The molecular weight of the polymeric backbone portion of the copolymer is chosen to be such that the molecule that is the synthetic precursor to the copolymer is soluble in the organic solvents used in the reaction, and the resulting copolymeric salt is stable in aqueous solution. The preferred molecular weight is between about 15 kilodaltons and about 200 kilodaltons. The weight ratio of the polymeric backbone in the hybridized copolymer of the present invention to the plurality of copolymeric side chains is selected so that the hybridized copolymer of the present invention provides for excellent water disperability of the hybridized copolymer. The preferred weight ratio of the polymeric backbone in the hybridized copolymer of the present invention to the plurality of copolymeric side chains is between 10:90 and 60:40.

In addition to a hydrophobic functional polymeric backbone, the hybridized copolymer of the present invention also comprises a plurality of copolymeric side chains attached to the backbone, wherein one or more side chains comprises a reaction product of at least (i) a polymerizable unsaturated monomer and (ii) a polymerizable acid-containing unsaturated monomer. Both polymerizable unsaturated and polymerizable acid-containing unsaturated monomers are needed in construction of a plurality of side chains, but additional material may be incorporated within any of the side chains.

The polymerizable unsaturated monomer that is the basis for one type of a building unit of the side chains is selected from a group consisting of an acrylate monomer, an alkacrylate monomer, an aromatic vinyl monomer, an aliphatic vinyl monomer, a vinyl ester monomer, a vinyl cyanogen-containing monomer, a halogenoid monomer, an olefin monomer, and a diene monomer.

The polymerizable acid-containing unsaturated monomer which is the basis for one type of a building unit of the side chains is selected from a group consisting of an acid-containing acrylate, an acid-containing methacrylate, an acid-containing vinyl monomer, an acid-containing alkylallyl monomer, a monocarboxylic acid-containing alkene, a dicarboxylic acid-containing alkene, a salt of any of the preceding, and an ester of any of the preceding.

The advantage of the hybridized copolymer is to provide water based jet ink which when printed yields excellent adhesion properties on low energy surfaces and provides stability against common cleaners.

The hybridized copolymer may be easily mixed with water, to yield a homogenous mixture. Such an aqueous mixture may be characterized as a manufacturing use product, which may then be further used in the process of preparing a liquid ink. The aqueous mixture of the hybridized copolymer may comprise a colloidal dispersion suitable for use in preparation of a water based jet ink vehicle, wherein the particle size of more than 60% of particles of the dispersion is less than 400 nanometers. Preferably, the particle size of more than 80% of particles in the dispersion is less than 200 nanometers. More preferably, the particle size of more than 90% of particles in the dispersion is less than 150 nanometers. The particle size refers to the median size of particles of the hybridized copolymer.

The hybridized copolymer as described herein is particularly suitable for use in formulating a liquid ink. The liquid ink so formulated with the hybridized copolymer may be used in any type of liquid ink, but the hybridized copolymer is particularly suitable for jet ink. Jet ink, otherwise known as inkjet ink, is used in inkjet printers that create an image by propelling droplets of such ink onto a substrate. The jet ink as herein may be used within the continuous inkjet technology, thermal drop-on-demand technology, or piezoelectric drop-on-demand technology.

A liquid ink formulation of the present invention comprises about 4 to about 9 weight percent hybridized copolymer, about 1 to about 5 weight percent pigment or dye, 0 to about 25 weight percent of additives required for performance such as antimicrobial agents, co-solvents or UV stabilizers and balance is water.

The liquid ink of the present invention may be applied to any substrate on which inkjet inks are typically applied, including porous materials. The liquid ink of the present invention is also suitable for use on both high surface energy substrates and low energy substrates.

Upon application of the liquid ink to the substrate, the volatile portions of the ink evaporate, leaving behind a residue or a coating on the substrate. The coating on the non-porous substrate is found on the surface of the substrate. The adhesion of the coating to the non-porous substrate is a crucial characteristic of the liquid ink. Surprisingly, the liquid ink of the present invention upon application to a polymeric substrate and evaporation of the volatile components of the ink yields a coating on the substrate that exhibits good adhesion.

Another aspect of the present invention is the process for preparing the hybridized copolymer, which may be used for preparation of the liquid ink. There are three processes that can be used to prepare the hybridized copolymer: three part synthesis process, two part synthesis process, and single part synthesis process.

In the three part synthesis process for preparing the hybridized copolymer, comprises the steps of

(a) reacting a functionalized hydrophobic polymer of an average molecular mass from about 15 to about 200 kilodaltons, with a hybridizing compound to create a reaction mixture;

(b) adding a first monomer component to the reaction mixture;

(c) adding a second monomer component to the reaction mixture; and

(d) neutralizing the reaction mixture with a base;

wherein the hydrophobic polymer is selected from the group consisting of a polysiloxane polymer, a polyolefin polymer, a polyvinyl polymer, and a copolymer thereof;

wherein either of the monomer components or both of the monomer components comprise a polymerizable unsaturated monomer; and

wherein either of the monomer components or both of the monomer components comprises a polymerizable acid-containing unsaturated monomer.

In step (a) of the three-part synthesis of the hybridized copolymer, the functionalized hydrophobic polymer is reacted with a hybridizing compound. The reaction mixture at the end of step (a) comprises the reaction product of the reaction of the functionalized hydrophobic polymer with a hybridizing compound, any compound that was added in excess, and other compounds, such as a solvent, or an initiator.

The functionalized hydrophobic polymer is a functionalized polysiloxane polymer, or a functionalized polyolefin polymer, or a functionalized polyvinyl polymer, or a copolymer of any of these three functionalized polymers. Under a preferred embodiment the functionalized hydrophobic polymer is a functionalized hydrophobic copolymer.

The functionalized hydrophobic polymer described above is reacted with a hybridizing compound. The hybridizing compound is a compound that reacts with at least one of the functionalized groups on the functionalized hydrophobic polymer, so that additional monomers may be added to the functionalized hydrophobic polymer via a polymerization reaction. The hybridizing compound reacts with the functional group of the functionalized hydrophobic polymer to yield a functionalized hydrophobic polymer substituted with a plurality of alkene groups (CR═CH₂, wherein R is H or C₁ to C₃ alkyl group). The hybridizing compound comprises (1) a first functional group that is an alkene or is easily converted into an alkene, (2) a second functional group that is capable of reacting readily to the functional group of the functionalized hydrophobic polymer, to generate a bond between the former functionalized hydrophobic polymer and a portion of the former hybridizing compound, and (3) a divalent bridging group connecting the first functional group and the second functional group.

In step (b), the first monomer component is added to the reaction mixture. Upon addition of the first monomer component, the monomers comprising the first monomer component react with the reaction product of functionalized hydrophobic polymer and hybridizing compound, to create a hybridized copolymer intermediate. The first monomer component upon exposure to the reaction mixture reacts with the alkene groups on the functionalized hydrophobic polymer that has been reacted with the hybridizing compound, wherein the alkene corresponds to the first functional group on the hybridizing compound.

In step (c), the second monomer component is added to the reaction mixture. Upon addition of the second monomer component, the monomers comprising the second monomer component react with the hybridized copolymer intermediate to create a pre-neutralized hybridized copolymer.

In step (d), the pre-neutralized hybrid copolymer is then neutralized with an acid. The neutralization of the pre-neutralized hybrid copolymer completes the formation of the hybrid copolymer. The hybrid copolymer may then be further neutralized, processed or diluted in the preparation of a liquid ink.

In the preparation of the hybridized copolymer, either of the monomer components or both of the monomer components comprise a polymerizable unsaturated monomer.

The polymerizable unsaturated monomer that is the basis of one type of repeating units within the side chain of hybrid copolymer has the formula

CH₂═C(R²)—X—Y—R¹,  (Formula 1)

wherein

—R² is H, halogen, or C₁ to C₃ alkyl group;

—X— is a bond, —CO—O, or —O—CO—;

—Y—0 is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H, halogen, —OH, or —CN;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

The polymerizable acid-containing unsaturated monomer which is the basis for one type of a building unit of the side chains is selected from a group consisting of an acid-containing acrylate, an acid-containing methacrylate, an acid-containing vinyl monomer, an acid-containing alkylallyl monomer, a monocarboxylic acid-containing alkene, a dicarboxylic acid-containing alkene, a salt of any of the preceding, and an ester of any of the preceding. The polymerizable acid-containing unsaturated monomer the basis of one type of repeating units within the side chain of hybrid copolymer under one embodiment has the formula

R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m),

wherein

R^(o4)— is H, C₁ to C₃ alkyl group, or an aryl group;

—R^(o2) is H, halogen, or C₁ to C₃ alkyl group;

—X^(o) is a bond, or —CO—O—;

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups; —R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding; and

m=1 or 2.

The polymerizable acid-containing unsaturated monomer that is the basis of one type of repeating units within the side chain of hybrid copolymer under another embodiment has the formula,

wherein T¹, T², and T³, are each independently H, a C₁ to C₃ alkyl group, carboxylic group, or a C₁ to C₃ alkyl carboxylic group, provided that acid-containing unsaturated monomer comprises two —COOH groups.

The copolymeric side chains that are attached to the hydrophobic functional polymeric backbone may optionally comprise additional components. Such components may be added within the structure of side chains, and may be used to improve the physical or chemical properties of the hybridized copolymer, such as the stability of the ink. One such component is a structural unit that acts as a UV absorber.

Another aspect of the present invention is the process for preparing the hybridized copolymer by a two-part synthesis process. In the two-part synthesis process for preparing the hybridized copolymer, the process comprises the steps of

(a) reacting a functionalized hydrophobic polymer of an average molecular mass from about 15 to about 200 kilodaltons, with a hybridizing compound to create a reaction mixture;

(b) adding a monomer component to the reaction mixture; and

(c) neutralizing the reaction mixture with a base;

wherein the hydrophobic polymer is selected from the group consisting of a polysiloxane polymer, a polyolefin polymer, and a polyvinyl polymer or a copolymer thereof; and

wherein the monomer component comprises a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer.

In step (a) of the two-part synthesis of the hybridized copolymer, the functionalized hydrophobic polymer is reacted with the hybridizing compound. This step is similar to step (a) of the three-part synthesis of the hybridized copolymer. The definition of the functionalized hydrophobic polymer, and the hybridizing compound, as used in the two-part synthesis is the same as for the three-part synthesis.

In step (b), the monomer component is added to the reaction mixture. Upon addition of the monomer component, the monomers comprising the monomer component react with the reaction product of functionalized hydrophobic polymer and hybridizing compound, to create a pre-neutralized hybrid copolymer. The monomer component upon exposure to the reaction mixture polymerizes with the alkene groups on the functionalized hydrophobic polymer that has been reacted with the hybridizing compound, wherein the alkene corresponds to the first functional group on the hybridizing compound.

The reaction of the monomer component with the reaction product of the functionalized hydrophobic polymer and hybridizing compound results in the pre-neutralized hybrid copolymer. In step (c), the pre-neutralized hybrid copolymer is neutralized with a base. The neutralization of the pre-neutralized hybrid copolymer completes the formation of the hybrid copolymer. The hybrid copolymer may then be further neutralized, processed, or diluted in the preparation of a liquid ink.

Another aspect of the present invention is the process for preparing the hybridized copolymer by a one-part synthesis process. In the one part synthesis process for preparing the hybridized copolymer, the process comprises the steps of

(a) mixing a functionalized hydrophobic polymer of an average molecular mass from about 15 to about 200 kilodaltons, a hybridizing compound, a polymerizable unsaturated monomer, and a polymerizable acid-containing unsaturated monomer to create a reaction mixture;

(b) delivering energy to the reaction mixture to cause a polymerization reaction to occur within the reaction mixture; and

(c) neutralizing the reaction mixture with a base;

wherein the hydrophobic polymer is selected from the group consisting of a polysiloxane polymer, a polyolefin polymer, and a polyvinyl polymer, or a copolymer thereof.

In step (a) of the one part synthesis of the hybridized copolymer, the functionalized hydrophobic polymer is mixed with the hybridizing compound, as well as with the polymerizable unsaturated monomer, and the polymerizable acid-containing unsaturated monomer.

In order for the functionalized hydrophobic polymer, the hybridizing compound to react, and further, in order for the polymerizable unsaturated monomer, and polymerizable acid-containing unsaturated monomer to polymerize with the reaction product of the functionalized hydrophobic polymer and the hybridizing compound, a sufficient energy must be delivered to the reaction mixture in order to traverse the activation energies of reactions. The energy may be delivered by heating, radiation, shear mixing, or sonication. Alternatively, the activation energies of the various reactions may be lowered by a serial addition of appropriate initiators and catalysts.

The reaction of the polymerizable unsaturated monomer and the polymerizable acid-containing unsaturated monomer with the reaction product of the functionalized hydrophobic polymer and hybridizing compound results in the pre-neutralized hybrid copolymer. In step (c) of the one part synthesis, the pre-neutralized hybrid copolymer is neutralized with a base.

DETAILED DESCRIPTION

One of the purposes of this invention is to provide a durable, external surfactant free, anionic, water based jet ink polymer which when formulated into an ink jet ink provides printing that has an excellent adhesion to metal or plastic substrates. Such jet ink polymer is suitable performance replacement of solvent soluble polymers currently in commercial use. The use of the inks of the present invention enhances performance criteria such as print-head open time, ink stability under varying conditions, and resistance to typical water based cleaners.

Known conventional water based latex polymers contain small suspended insoluble organic polymers within a micellular structure the size of which can vary with changes in temperature or the addition of water miscible solvents or organic amines. The solubility characteristics of the new polymer eliminate such problems.

The practice of the present invention employs, unless otherwise indicated, conventional techniques of polymer chemistry, organic chemistry, and related fields, which are within the skill of art. See, for example, Paul C. Hiemenz, POLYMER CHEMISTRY: THE BASIC CONCEPTS, Marcel Dekker (1984); Sandler, Karo, Bonesteel and Pearce, POLYMER SYNTHESIS AND CHARACTERIZATION, Academic Press (1998).

As used in the specification and claims, the singular form “a”, “an” and “the” include plural references unless the context clearly dictates otherwise. For example, the term “a monomer” includes a plurality of monomers, including mixtures of monomers.

As used herein, the term “comprising” is intended to mean that the defined compositions and methods include the recited elements, but not necessarily exclude others. “Consisting essentially of” when used to define compositions and methods, shall mean to exclude other elements of any essential significance to the combination. Thus, a composition consisting essentially of the elements as defined herein would not exclude trace contaminants from the isolation and purification methods. “Consisting of” shall mean to exclude more than trace elements of other ingredients. Embodiments defined by each of these transition terms are within the scope of this invention.

All numerical designations, such as, weight, pH, temperature, time, concentration, and molecular weight, including ranges, are approximations that are varied by 10%. It is to be understood, although not always explicitly stated, that all numerical designations are preceded by the term “about.” It also is to be understood, although not always explicitly stated, that the reagents described herein are merely exemplary and that equivalents of such are known in the art.

The term “functional” when referring to a polymeric portion of a molecule means that the polymer portion of the molecule has covalent bonds to other portions of the molecule.

The phrase “functionalized polymer” refers to a polymer that contains functional groups. Such functional groups are typically reactive towards other reactants, which may be useful in synthesis of further polymers. Examples of such functional groups include hydroxide or carboxylic acid.

The phrase “hydrophobic polymer” refers to non-polar polymers that contain a relatively small proportion of oxygen or nitrogen atoms.

The term “low surface energy” when referring to a surface or a substrate, means a hydrophobic surface exhibiting an average surface energy of about 40 dynes/cm or less.

The phrase “molecular weight” when referring to a polymer means average molecular weight. This phrase also refers not only to the weight of a molecule, but also to the weight of a portion of a molecule, thus, for example, the phrase “molecular weight of the polymeric backbone” refers to the average molecular weight of the polymeric backbone portion of the molecule, and not to the average molecular weight of the molecule that contains the polymeric backbone portion of the molecule.

The term “polymer” refers to a large molecule composed of repeating structural units. Such repeating units are building blocks provided by polymerized monomers. Unless specifically excluded, the term “polymer” is a mixture of large molecules composed of repeating structural units. Further, unless specifically excluded, the term “polymer” also refers to copolymers.

The term “substrate” refers to any material onto which a liquid ink is applied.

The phrase “water based” when referring to a polymer means that the polymer is in a stable, homogeneous phase with water. The polymer may be dissolved in water, or the polymer may be in a stable suspension in water, or the polymer may be a stable sol in water, or the polymer may be a stable dispersion in water.

The term “mixture” refers to any composition that comprises more than one substance. The term refers to both a homogeneous and heterogeneous mixture. The term refers to any composition that comprises more than one substance, regardless of the morphology of the substances or the phase thereof. Thus, the term includes a solution, a suspension, a dispersion, a sol, a foam, a gel, an amalgam, an alloy, and like.

The name of an element when used to refer to a substituent or to a portion of a molecule or a polymer means that one of more atoms of that element are incorporated within the structure of that molecule, regardless whether the atom is found in the molecule as defined by the class the molecule or not. For example, the nitrogen in the phrase “a nitrogen-containing acrylamide” refers to both the nitrogen which is a part of the amide group, and to any nitrogen-containing groups that may be a substituent on the acrylamide.

The name of an element, or a group of elements, when used to refer to a substituent or to a portion of a molecule or a polymer, is used regardless of the oxidation state of that atom. For example, the term “a halogen” includes within its definition a halide.

One of the aspects of the present invention is a hybridized copolymer comprising

(a) a hydrophobic functional polymeric backbone of an average molecular mass from about 15 to about 200 kilodaltons, wherein the functional polymeric backbone comprises a polymer selected from the group consisting of a functional polysiloxane polymer, a functional polyolefin polymer, and a functional polyvinyl polymer; and

(b) a plurality of copolymeric side chains attached to the backbone, wherein one or more side chains comprises a reaction product of at least a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer.

The hybridized copolymer may have many uses within the coating and film applications, but it is especially useful as a binder component in ink jet inks.

The hybridized copolymer is a graft copolymer. A graft copolymer is branched co-polymer wherein the side chains are structurally distinct from the backbone. In the present invention the backbone of the graft copolymer is the hydrophobic functional polymeric backbone, and the side chains are copolymeric side chains attached to the backbone.

The copolymer of the present invention comprises at least a backbone and a plurality of copolymeric side chains. The backbone is a hydrophobic functional polymeric chain.

The polymeric chain that comprises the backbone can be either a functional homopolymer or a functional copolymer. The backbone comprises a functional polysiloxane polymer, a functional polyolefin polymer, a functional polyvinyl polymer, or any copolymer of the three.

Under a preferred embodiment the backbone is a functional copolymer.

The functional polyolefin polymer is a polyolefin polymer that has covalent bonds to other parts of the molecule, namely to copolymeric side chains. Polyolefin polymer is a polymer produced from one or more alkene monomers with a general formula C_(n)H_(2n), wherein n is 2 to 8. Such alkenes may be linear or branched. Examples of alkenes include ethylene, propylene, butylene, pentene, and hexene. Examples of suitable polyolefins include functional polyethylene, functional polypropylene, functional polybutene, functional polyisobutylene, functional polymethylpentene, and copolymers thereof.

Under one embodiment of the present application, the polyolefin that is used in preparation of the hybridized copolymer of the present application is a polyolefin that acts as an adhesion promoter to TPO and polypropylene. Such adhesion promoter may be either chlorinated or non-chlorinated. Under one embodiment the adhesion promoter is non-chlorinated.

The functional polyvinyl polymer is a polyvinyl polymer that has covalent bonds to other parts of the molecule, namely copolymeric side chains. Polyvinyl polymer is a polymer produced from one or more vinyl monomers. Examples of vinyl monomers include vinyl chloride, vinyl acetate, and maleic acid. Examples of suitable polyvinyl polymers include polyvinyl chloride, polyvinyl acetate, and copolymers thereof.

Particularly suitable polyvinyl polymers are copolymers of vinyl chloride, vinyl acetate and maleic acid. It is a surprising and unexpected result that one of the preferred polyvinyl vinyl polymers comprises copolymer based on about 60% to 95% vinyl chloride, 2% to 10% vinyl acetate, and 1% to 10% maleic acid.

The functional polysiloxane polymer is a polysiloxane polymer that has covalent bonds to other parts of the molecule, namely copolymeric side chains. Polysiloxane polymer is a linear polymer of formula [RR′SiO]_(n), wherein R and R′ are same or different organic groups such as hydrogen, alkyl, aryl, alkylaryl. Such alkyl groups may be linear or branched. Examples of suitable functional polysiloxane polymer include functional polydimethylsiloxane, functional polymethylhydrosiloxane, functional poly(methylhydro-co-dimethyl)siloxane, functional polyethylhydrosiloxane, functional polyphenyl-(dimethylhydro)siloxane, functional methylhydrosiloxane-phenylmethylsiloxane copolymer, functional methylhydrosiloxane-octylmethylsiloxane copolymer, and co-polymers of any two or more thereof.

Although the polymeric backbone may comprise a copolymer of functional polysiloxane units, or a copolymer of a functional polyolefin units, or a copolymer of a functional polyvinyl units, the polymeric backbone in the copolymer of the present invention may also be a copolymer of any of these three copolymers. It has been found that particularly useful is a copolymer of the present invention wherein the polymeric backbone is a copolymer of a functional polyvinyl polymer and a functional polysiloxane polymer. Alternatively, the backbone may comprise a copolymer of a functional polyvinyl polymer and a functional polyolefin polymer. Furthermore, the backbone may comprise a copolymer of a functional polyvinyl polymer, a functional polysiloxane polymer, and a functional polyolefin polymer.

In addition, the hybridized copolymer of the present application may be a mixture of molecules that have different backbones. One example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer and a hybridized copolymer comprising a functional polyolefin polymer.

A second example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer and a hybridized copolymer comprising a functional polyvinyl polymer.

A third example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer and a hybridized copolymer comprising a functional polyvinyl polymer.

A fourth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A fifth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A sixth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A seventh example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

An eighth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A ninth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A tenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

An eleventh example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A twelfth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A thirteenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A fourteenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A fifteenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A sixteenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A seventeenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

An eighteenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A nineteenth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a functional polysiloxane polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A twentieth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a functional polysiloxane polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A twenty-first example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a functional polysiloxane polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A twenty-second example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A twenty-third example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A twenty-fourth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A twenty-fifth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A twenty-sixth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A twenty-seventh example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A twenty-eighth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A twenty-ninth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A thirtieth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A thirty-first example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A thirty-second example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A thirty-third example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A thirty-fourth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A thirty-fifth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A thirty-sixth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyolefin polymer, a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

A thirty-seventh example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer.

A thirty-eighth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer, and a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyvinyl polymer.

A thirty-ninth example is the hybridized copolymer that is a mixture of a hybridized copolymer comprising a functional polyvinyl polymer, a hybridized copolymer comprising a functional polysiloxane polymer, a hybridized copolymer comprising a copolymer of functional polysiloxane polymer and functional polyolefin polymer, and a hybridized copolymer comprising a copolymer of functional polyolefin polymer and functional polyvinyl polymer.

The molecular weight of the polymeric backbone portion of the copolymer is chosen to be such that the molecule that is the synthetic precursor to the copolymer is soluble in organic solvents used in the reaction. The preferred molecular weight is between about 15 kilodaltons and about 200 kilodaltons.

The weight ratio of the polymeric backbone in the hybridized copolymer of the present invention to the plurality of copolymeric side chains is selected so that the hybridized copolymer of the present invention provides for excellent water disperability of the hybridized copolymer. The preferred weight ratio of the polymeric backbone in the hybridized copolymer of the present invention to the plurality of copolymeric side chains is between 10:90 and 60:40.

In addition to a hydrophobic functional polymeric backbone, the hybridized copolymer of the present invention also comprises a plurality of copolymeric side chains attached to the backbone, wherein one or more side chains comprises a reaction product of at least (i) a polymerizable unsaturated monomer and (ii) a polymerizable acid-containing unsaturated monomer. Both polymerizable unsaturated and polymerizable acid-containing unsaturated monomers are needed in construction of at plurality of side chains, but additional material may be incorporated within any of the side chains.

The polymerizable unsaturated monomer that is the basis for one type of a building unit of the side chains is selected from a group consisting of an acrylate monomer, an alkacrylate monomer, an aromatic vinyl monomer, an aliphatic vinyl monomer, a vinyl ester monomer, a vinyl cyanogen-containing monomer, a halogenoid monomer, an olefin monomer, and a diene monomer. Although only one kind of a polymerizable unsaturated monomer may be used in preparation of any of the side chains, typically a several kinds of polymerizable unsaturated monomers are used.

The polymerizable unsaturated monomer that is the basis of one type of repeating units within the side chain of hybrid copolymer has the formula

CH₂═C(R²)—X—Y—R¹,  (Formula 1)

wherein

—R² is H, halogen, or C₁ to C₃ alkyl group;

—X— is a bond, —CO—O—, or —O—CO—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H, halogen, —OH, or —CN;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

A halogen is an atom of the 17th Group of the period table, which includes fluorine, chlorine, bromine and iodine.

C₁ to C₃ alkyl group is a methyl group, ethyl group, n-propyl group, or a i-propyl group.

C₁ to C₂₂ bridging alkyl group is a saturated bridging group of formula —(CH₂)_(n)— wherein n is an integer 1 to 22. The term “alkyl” as used to refer to a bridging group, a divalent group, is referred under current IUPAC rules as “alkdiyl” group. This bridging group may be further substituted anywhere along the chain by a small terminal alkyl group such as methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomer any of the foregoing.

In cases when —X— is a bond, the formula CH₂═C(R²)—X—Y—R¹, is reduced to formula CH₂═C(R²)—Y—R¹. Likewise, when —Y— is a bond, the formula CH₂═C(R²)—X—Y—R¹, is reduced to formula CH₂═C(R²)—Y—R¹. Furthermore, when both —X— and —Y— are bonds, the formula CH₂═C(R²)—X—Y—R¹, is reduced to CH₂═C(R²)—R¹.

The symbol —CN refers to a cyanyl group. The cyanyl group should be chemically inert vis-à-vis conditions in which the copolymer may be exposed in order to avoid hydrolysis of the cyanyl group.

Under one embodiment of the present invention, the polymerizable unsaturated monomer that is the basis for the side chains is an acrylate monomer, an alkacrylate monomer, or both. The acrylate monomer is of formula CH₂═C(R²)—X—Y—R¹, wherein

—R² is H;

—X— is —CO—O—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H or —OH;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy; or

(6) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe.

The acrylate monomer is also of formula CH₂═CH—CO—O—Y—R¹, wherein

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H or —OH;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy; or

(6) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe.

Examples of a suitable acrylate include 2-hydroxyethyl acrylate, HEA, ethyl acrylate, methyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, n-pentyl acrylate, n-amyl acrylate, i-pentyl acrylate, isoamyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, i-octyl acrylate, decyl acrylate, isodecyl acrylate, dodecyl acrylate, lauryl acrylate, octadecyl acrylate, isobornyl acrylate, phenyl acrylate, benzyl acrylate, ethylene glycol methyl ether acrylate, glycidyl acrylate, and mixtures thereof. Under one embodiment of the invention the acrylate monomers that are the basis of the copolymeric side chain is 2-hydroxylethyl acrylate, ethyl acrylate, or a mixture thereof.

The alkylacrylates monomer is of formula CH₂═C(R²)—X—Y—R¹, wherein

—R² is C₁ to C₃ alkyl;

—X— is —CO—O—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with OH or OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

One example of an alkylacrylate monomer is a methacrylate. Methacrylate has a formula

CH₂═C(R²)—X—Y—R¹,

wherein

—R² is C₁ alkyl;

—X— is —CO—O—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with OH or OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

C₁ alkyl is a methyl group.

The methacrylate monomer is also of formula

CH₂═CMe-CO—O—Y—R¹,

wherein

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with OH or OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

Examples of suitable methacrylates include methyl methacrylate, MMA, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, s-butyl methacrylate, t-butyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, behenyl methacrylate, lauryl methacrylate, isobornyl methacrylate (IBOMA), phenyl methacrylate, benzyl methacrylate, 1-naphthyl methacrylate, (trimethylsilyl)methacrylate, 9-anthracenylmethyl methacrylate, glycidyl methacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, and ethylene glycol propylene glycol monomethacrylate. Under one embodiment of the invention the methacrylate monomers that are the basis of the copolymeric side chain is methyl 2-methacrylate, behenyl methacrylate, or a mixture thereof.

The aromatic vinyl monomer is of formula CH₂═C(R²)—R¹,

wherein

—R² is H or a C₁ to C₃ alkyl group;

—R¹ is a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and a C₁ to C₃ alkyloxy.

An aryl group is any hydrocarbon cyclic group that follows the Hückel Rule. Such an aryl group may be single aromatic ring group, bicyclic aromatic ring group, or tricyclic aromatic ring group. An example of a single aromatic ring group is the phenyl group. An example of a bicyclic aromatic ring group is naphthalene. An example of a tricyclic aromatic ring group is anthracene. The aromatic group may be optionally substituted with one or more of any of the following: fluorine, chlorine, bromine, iodine, methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propyloxy, including any isomers thereof.

Examples of a suitable aromatic vinyl monomer include styrene, alpha-methylstyrene, vinyl toluene, 4-t-butylstyrene, chlorostyrene, vinylanisole, and vinyl naphthalene.

The vinyl ester monomer is of formula

CH₂═CH—O—CO—Y—R¹,

wherein

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H, a halogen, —OH, or —CN;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

An example of a suitable vinyl ester is vinyl acetate.

The vinyl cyanogen-containing monomer is an unsaturated monomer of Formula 1 that comprises a —CN group. Examples of cyanogen-containing monomer include acrylonitrile and methacrylonitrile.

The halogenoid monomer is an unsaturated monomer of Formula 1 that comprises one or more halogens. Examples of a halogen include fluorine, chlorine, bromine and iodine. An example of a halogenoid comprising one halogen is vinyl chloride. An example of a halogenoid comprising two halogens is vinylidene chloride.

The olefin monomer is of formula

CH₂═C(R²)—Y—R¹,

wherein

—R² is H, or C₁ to C₃ alkyl group;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is H.

Examples of an olefin monomer include ethylene and propylene.

The diene monomer is of formula

CH₂═CH—Y—CZ═CH₂,

wherein

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

Z is H or a halogen.

An example of a diene monomer when Z═H is butadiene. An example of a diene monomer when Z is a halogen is chloroprene.

The polymerizable acid-containing unsaturated monomer which is the basis for one type of a building unit of the side chain is selected from a group consisting of an acid-containing acrylate, an acid-containing methacrylate, an acid-containing vinyl monomer, an acid-containing alkylallyl monomer, a monocarboxylic acid-containing alkene, a dicarboxylic acid-containing alkene, a salt of any of the preceding, and an ester of any of the preceding. Although only one kind of a polymerizable acid-containing unsaturated monomer may be used in preparation of any of the side chains, typically a several kinds of polymerizable acid-containing unsaturated monomers are used.

The acid-containing acrylate is any acrylate monomer that has an acid group on the same molecule. Examples of acid-containing acrylates include acrylic acid, a carboxylalkyl acrylate, a sulfoalkyl acrylate, and an alkene glycol acrylate phosphate.

The carboxylalkyl acrylate is any acrylate monomer that has a carboxylic acid group on the same molecule. The term “carboxyl acid group” means —C(O)—OH. Examples of carboxylalkyl acrylates include 2-carboxyethyl acrylate, carboxylmethyl acrylate, 3-carboxylpropyl acrylate, and 4-carboxybutyl acrylate.

The sulfoalkyl acrylate is any acrylate monomer that has a sulfoalkyl acid group on the same molecule. The term “sulfoalkyl acid group” means an alkyl group that comprises a —SO₃H group. Examples of sulfoalkyl acrylates include 2-sulfoethyl acrylate, sulfomethyl acrylate, 3-sulfopropyl acrylate, and 4-sulfobutyl acrylate.

The alkene glycol acrylate phosphate is any acrylate monomer that has a phosphoric acid group on the same molecule. The term “phosphoric acid group” means an alkyl group that comprises a phosphate group, or —OP(O)(OH)₂ group. Examples of alkene glycol acrylate phosphate include ethylene glycol acrylate phosphate, propylene glycol acrylate phosphate, and butylene glycol acrylate phosphate.

The acid-containing methacrylate is any methacrylate monomer that has an acid group on the same molecule. Examples of acid-containing methacrylates include methacrylic acid, a carboxylalkyl methacrylate, a sulfoalkyl methacrylate, and an alkene glycol methacrylate phosphate.

The carboxylalkyl methacrylate is any methacrylate monomer that has a carboxylic acid group on the same molecule. The term “carboxyl acid group” means —C(O)—OH. Examples of carboxylalkyl methacrylates include 2-carboxyethyl methacrylate, carboxylmethyl methacrylate, 3-carboxylpropyl methacrylate, and 4-carboxybutyl methacrylate.

The sulfoalkyl methacrylate is any methacrylate monomer that has a sulfoalkyl acid group on the same molecule. The term “sulfoalkyl acid group” means an alkyl group that comprises a —SO₃H group. Examples of sulfoalkyl methacrylates include 2-sulfoethyl methacrylate, sulfomethyl methacrylate, 3-sulfopropyl methacrylate, and 4-sulfobutyl methacrylate.

The alkene glycol methacrylate phosphate is any methacrylate monomer that has a phosphoric acid group on the same molecule. The term “phosphoric acid group” means an alkyl group that comprises a phosphate group, or —OP(O)(OH)₂ group. Examples of alkene glycol methacrylate phosphate include ethylene glycol methacrylate phosphate, propylene glycol methacrylate phosphate, and butylene glycol methacrylate phosphate.

The acid-containing vinyl monomer is any molecule that has a vinyl group —CH═CH₂, and an acid group. The acid group may be a carboxylic group, a sulfonic acid group or a phosphoric acid group. Examples of acid-containing vinyl monomers include 4-vinylbenzoic acid, 4-styrenesulfonic acid, 1-vinyl-1H-pyrrole-2-carboxylic acid, 4-ethyl-5-phenyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-(4-methoxyphenyl)-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-p-tolyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 2-vinyl-1,1-cyclopropanedicarboxylic acid, 2-isopropyl-6-methyl-3-vinyl-6-heptenoic acid, and vinyl sulfonic acid.

The acid-containing alkylallyl monomer is any alkylallyl monomer that has an acid group on the same molecule. The term alkylallyl refers to CH₂═C(R^(o2))—, wherein R^(o2) is an alkyl group. Examples of acid-containing alkylallyl monomers include methylallyl sulfonic acid.

The monocarboxylic acid-containing alkene is a molecule that contains an aliphatic carbon-carbon double bond, and also a single carboxylic acid group. The aliphatic carbon-carbon double bond can be at the end, or anywhere else in the molecule. In order to be useful for the preparation of the hybridized copolymer, the double bond must be polymerizable. Examples of monocarboxylic acid-containing alkene include crotonic acid, isocrotonic acid, and cinnamic acid.

The dicarboxylic acid-containing alkene is a molecule that contains an aliphatic carbon-carbon double bond, and also two carboxylic acid groups. The aliphatic carbon-carbon double bond can be at the end, or anywhere else in the molecule. With respect to the aliphatic carbon-carbon double bond, the carboxylic acid groups are on parts of molecules that are cis, trans, or gem to each other. In order to be useful for the preparation of the hybridized copolymer, the double bond must be polymerizable. Examples of dicarboxylic acid-containing alkenes include fumaric acid, itaconic acid, mesaconic acid, citraconic acid, and maleic acid.

The definition of polymerizable acid-containing unsaturated monomer also includes a salt of any of the preceding, and an ester of any of the preceding. The term “salt” refers to the complex that is made by replacing the acidic proton with a cationic moiety in the polymerizable acid-containing unsaturated monomer of any of the foregoing definitions. The term “ester” of any of the preceding refers to the molecule made by replacing the acidic proton with an alkyl group in the polymerizable acid-containing unsaturated monomer of any of the foregoing definitions.

The polymerizable acid-containing unsaturated monomer that is the basis of one type of repeating units within the side chain of hybrid copolymer under one embodiment has the formula

R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m),

wherein

R^(o4)— is H, C₁ to C₃ alkyl group, or an aryl group;

—R^(o2) is H, halogen, or C₁ to C₃ alkyl group;

—X^(o)— is a bond, or —CO—O—;

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups;

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding; and

m=1 or 2.

C₁ to C₃ alkyl group is a methyl group, ethyl group, n-propyl group, or an i-propyl group.

C₁ to C₁₈ bridging alkyl group is a saturated bridging group of formula —(CH₂)_(n)— wherein n is an integer 1 to 18. The term “alkyl” as used when referring to a bridging group, is a divalent group based on an alkane, and is referred to under current IUPAC rules as “alkdiyl” group. This bridging group may be further substituted anywhere along the chain by a small terminal alkyl group such as methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomer any of the foregoing.

The term “cycloalkyl” refers to optionally substituted monocyclic, bicyclic or tricyclic hydrocarbon groups of three to twelve carbon atoms, each of which may contain one or more carbon to carbon double bonds, or the cycloalkyl may be substituted by one or more substituents, such as alkyl, halo, oxo, hydroxy, alkoxy, alkanoyl, acylamino, carbamoyl, cyano, and like.

In cases when —X^(n)— is a bond, the formula R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m), is reduced to formula R^(o4)—CH═C(R^(o2))—Y^(o)—(R^(o1))_(m). Likewise, when —Y^(n)— is a bond, the formula R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m), is reduced to formula R^(o4)—CH═C(R^(o2))—X^(o)—(R^(o1))_(m). Furthermore, when both —X^(n)— and —Y^(n)— are bonds, the formula R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m), is reduced to R^(o4)—CH═C(R^(o2))—(R^(o1)).

The polymerizable acid-containing unsaturated monomer that is the basis of one type of repeating units within the side chain of hybrid copolymer under another embodiment has the formula,

wherein T¹, T², and T³, are each independently H, a C₁ to C₃ alkyl group, carboxylic group, or a C₁ to C₃ alkyl carboxylic group, provided that acid-containing unsaturated monomer comprises two —COOH groups. The alkene compound has hydrogen, and three substituents, T¹, T², and T³, bound to the double bond. Group T¹ is trans to group T². Group T¹ is cis to group T³. Group T² is gem to group T³. The two —COOH groups can be bound directly to the alkene, or it can be bounded to the alkene via a C₁ to C₆ aliphatic bridging group.

Under one embodiment of the present invention, the polymerizable acid-containing unsaturated monomer that is the basis for the side chains is an acid-containing acrylate monomer. The acid-containing acrylate monomer is of formula

CH₂═CH—CO—O—Y^(o)—R^(o1),

wherein

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

In cases where —Y^(o)— is a bond, —R^(o1) is H.

When the polymerizable acid-containing unsaturated monomer which is the basis for the side chains is an acid-containing acrylate monomer of formula CH₂═CH—CO—O—Y^(o)—R^(o1), then moiety —R^(o1) comprises the acid.

Examples of suitable polymerizable acid-containing acrylate includes acrylic acid, 2-carboxyethyl acrylate, carboxylmethyl acrylate, 3-carboxylpropyl acrylate, 4-carboxybutyl acrylate, sulfomethyl acrylate, 2-sulfoethyl acrylate, 3-sulfopropyl acrylate, 4-sulfobutyl acrylate, ethylene glycol acrylate phosphate, propylene glycol acrylate phosphate, and butylene glycol acrylate phosphate.

Under another embodiment of the present invention, the polymerizable acid-containing unsaturated monomer that is the basis for the side chains is an acid-containing methacrylate monomer. The acid-containing methacrylate monomer is of formula

CH₂═C(CH₃)—CO—O—Y^(o)—(R^(o1))_(m),

wherein

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

In cases where —Y^(o)— is a bond, —R^(o1) is H.

Examples of suitable polymerizable acid-containing methacrylate include methacrylic acid, carboxylmethyl methacrylate, 3-carboxylpropyl methacrylate, 4-carboxybutyl methacrylate, 2-carboxyethyl methacrylate, sulfomethyl methacrylate, 2-sulfoethyl methacrylate, 3-sulfopropyl methacrylate, 4-sulfobutyl methacrylate, ethylene glycol methacrylate phosphate, propylene glycol methacrylate phosphate, and butylene glycol methacrylate phosphate.

The acid-containing vinyl monomer has the formula

CH₂═CH—Y^(o)—(R^(o1))_(m),

wherein

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups;

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

Examples of suitable acid-containing vinyl monomer include 4-vinylbenzoic acid, 4-styrenesulfonic acid, 1-vinyl-1H-pyrrole-2-carboxylic acid, 4-ethyl-5-phenyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-(4-methoxyphenyl)-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-p-tolyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 2-vinyl-1,1-cyclopropanedicarboxylic acid, and vinyl sulfonic acid.

The acid-containing alkylallyl monomer has the formula

CH₂═C(R^(o2))—Y^(o)—R^(o1),

wherein

—R^(o2) is C₁ to C₃ alkyl group;

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups;

R^(o1) is —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

An example of suitable acid-containing alkylallyl monomer is methylallyl sulfonic acid.

The monocarboxylic acid-containing alkene that is the basis of one type of repeating units within the side chain of hybrid copolymer under one embodiment has the formula

R^(o4)—CH═C(R^(o2))—CO—OH,

wherein

R^(o4)— is C₁ to C₃ alkyl group, or an aryl group; and

—R^(o2) is H or C₁ to C₃ alkyl group.

C₁ to C₃ alkyl group is a methyl group, ethyl group, n-propyl group, or an i-propyl group.

The copolymeric side chains that are attached to the hydrophobic functional polymeric backbone may optionally comprise additional components. Such components may be added within the structure of side chains, and may be used to improve the physical or chemical properties of the hybridized copolymer, such as the stability of the ink. One such component is a structural unit that acts as a UV absorber. Such a UV absorber will dissipate the energy that is absorbed by the printed ink thus mitigating the aging process of the printed ink. Such a UV absorber will absorb the UV radiation and prevent the formation of free radicals. Examples of UV absorbers that may be incorporated into the side chains include benzophenones, hindered amine light stabilizers, benzotriazoles, nickel quenchers, 2-(2′-hydroxy-5′-methacryloyloxy ethylphenyl)-2-H-benzotriazole, Ruva 93, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate and methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate.

The hybridized copolymer as described herein may have many uses within the coating and film applications, but it is especially useful as a binder in inks, particularly water based jet inks.

The advantage of the hybridized copolymer is to provide water based jet ink which when printed yields excellent adhesion properties on low energy surfaces and provides stability against common cleaners.

The hybridized copolymer may be easily mixed with water, to yield a homogenous aqueous mixture. Such an aqueous mixture may be characterized as a manufacturing use product, which may then further used in the process of preparing of an ink. The definition of phrase “aqueous mixture” as referring to the aqueous mixture of hybridized copolymer also includes any aqueous mixture comprising the hybridized copolymer which may be conveyed to the same or another manufacturer of ink products, including a manufacturing intermediate, a partially formulated ink, or a fully formulated ink. The ink is preferably a jet ink.

The aqueous mixture of the hybridized copolymer may comprise a colloidal dispersion suitable for use in preparation of a water based jet ink vehicle, wherein the particle size of more than 60% of particles of the dispersion is less than 400 nanometers. Preferably, the particle size of more than 80% of particles in the dispersion is less than 200 nanometers. More preferably, the particle size of more than 90% of particles in the dispersion is less than 150 nanometers. The particle size refers to the median size of particles of the hybridized copolymer.

Stability testing of an aqueous mixture or a dispersion, of the hybridized polymer shows that the aqueous mixture is stable with respect to several physical characteristics, including viscosity and particle size distribution. Viscosity measurements via the Zahn cup showed that the viscosity of the aqueous mixture did not change within 10% after being exposed for 14 days at 60° C. Particle-size distribution measurements by static light scattering showed that the particle size distribution did not change within 10% after being held at 60° C. for 14 days.

Binders in jet inks are traditionally difficult to dissolve or disperse in an aqueous solution. To aide with the mixing, homogenization, dispersement or dissolution, a surfactant or a mixture of surfactants is typically added to the mixture. It is thus unexpected and not predictable that the hybridized copolymer of the present invention mixes well with water without the need to resort to a surfactant.

The aqueous mixture of the hybridized copolymer may further comprise an antimicrobial. The antimicrobial is a biocide added to the aqueous mixture to inhibit the growth of microorganisms. Examples of suitable antimicrobials include, sodium benzoate, sodium pentachlorophenol, sodium 2-pyridinethiol-1-oxide, sodium sorbate, sodium dehydroacetate, benzisothiazolinone, 1,2-dibenzothiazolin-3-one, methylisothiazolinone and chloromethylisothiazolinone. Commercially available biocides include Proxel™ CRL, Proxel™ BDN, Proxel™ GXL, Proxel™ XL-2, and Proxel™ TN (all Proxel™ microbials are available from Arch Chemicals, Smyrna, Ga.) and XBINX™ (available from PMC Specialties Group, Inc., Cincinnati, Ohio). Typically, a small amount, such as 0.05 to 5%, particularly 0.1 to 1%, and more particularly 0.2 to 0.4% by weight of biocide, is used in the aqueous mixture.

The hybridized copolymer as described herein is particularly suitable for use in formulating of a liquid ink. The liquid ink so formulated with the hybridized copolymer may any type of a liquid ink, but the hybridized copolymer is particularly suitable for jet ink. Jet ink, otherwise known as inkjet ink, is used in inkjet printers that create an image by propelling droplets of such ink onto a substrate. The jet ink as herein may be used within the continuous inkjet technology, thermal drop-on-demand technology, or piezoelectric drop-on-demand technology.

A liquid ink formulation of the present invention comprises about 4 to about 9 weight percent hybridized copolymer, about 1 to about 5 weight percent pigment or dye, 0 to about 25 weight percent of additives required for performance such as antimicrobial agents, biocides, co-solvents or UV stabilizers and balance is water.

The liquid ink may further comprise a co-solvent. Under one embodiment of the present invention the co-solvent is miscible with water. Examples of a water-miscible co-solvent include propylene glycol, 2-propanol, 1,2-hexanediol, propylene glycol methyl ether, dipropylene glycol methyl ether, diethylene glycol, diethylene dimethyl ether, diethylene glycol diethyl ether, Texanol™, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and methyl pyrrolidone.

When co-solvents are used, the liquid inks of the present invention are formulated to comprise about 4 to about 9 weight percent hybridized copolymer, about 1 to about 5 weight percent pigment or dye, up to about 15% co-solvent, up to about 1 to 3% of other specific additives required for performance such as biocides, antimicrobial agents, wetting agents, UV stabilizers, defoamers, and balance is water.

Under another embodiment of the present invention, the co-solvent is not fully miscible with water. Such a co-solvent may act on the interface of water and the hydrophobic portion of the copolymer. Such a co-solvent is absorbed into the hydrophobic portion of the hybridized co-polymer.

The pigment as used in the liquid ink is not particularly limited, and any of an inorganic pigment and an organic pigment may be used. Examples of the inorganic pigment include titanium oxide and iron oxide. Further, a carbon black produced by a known method such as a contact method, a furnace method, or a thermal method can be used.

Examples of the organic pigment include an azo pigment (such as an azo lake pigment, an insoluble azo pigment, a condensed azo pigment, or a chelate azo pigment), a polycyclic pigment (such as a phthalocyanine pigment, a perylene pigment, a perinone pigment, an anthraquinone pigment, a quinacridone pigment, a dioxazine pigment, a thioindigo pigment, an isoindolinone pigment, or a quinophthalone pigment), a dye chelate (such as a basic dye type chelate, or an acid dye type chelate), a nitro pigment, a nitroso pigment, Aniline Black or the like can be used.

Specific examples of the carbon black which is used as the black ink include No. 2300, No. 900, MCF88, No. 33, No. 40, No. 45, No. 52, MA7, MA8, MA100, and No. 2200B (all of which are manufactured by Mitsubishi Chemical Corporation), Raven 5750, Raven 5250, Raven 5000, Raven 3500, Raven 1255, and Raven 700 (all of which are manufactured by Columbian Chemicals Company), Regal 400R, Regal 330R, Regal 660R, Mogul L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, and Monarch 1400 (all of which are manufactured by Cabot Corporation), and Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color Black 5150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex V, Printex 1400, Special Black 6, Special Black 5, Special Black 4A, and Special Black 4 (all of which are manufactured by Degussa AG).

Specific examples of the pigment which is used in the yellow ink include C.I. Pigment Yellow 1, C.I. Pigment Yellow 2, C.I. Pigment Yellow 3, C.I. Pigment Yellow 12, C.I. Pigment Yellow 13, C.I. Pigment Yellow 14C, C.I. Pigment Yellow 16, C.I. Pigment Yellow 17, C.I. Pigment Yellow 73, C.I. Pigment Yellow 74, C.I. Pigment Yellow 75, C.I. Pigment Yellow 83, C.I. Pigment Yellow 93, C.I. Pigment Yellow 95, C.I. Pigment Yellow 97, C.I. Pigment Yellow 98, C.I. Pigment Yellow 109, C.I. Pigment Yellow 110, C.I. Pigment Yellow 114, C.I. Pigment Yellow 128, C.I. Pigment Yellow 129, C.I. Pigment Yellow 138, C.I. Pigment Yellow 150, C.I. Pigment Yellow 151, C.I. Pigment Yellow 154, C.I. Pigment Yellow 155, C.I. Pigment Yellow 180, and C.I. Pigment Yellow 185.

Specific examples of the pigment which is used in the magenta ink include C.I. Pigment Red 5, C.I. Pigment Red 7, C.I. Pigment Red 12, C.I. Pigment Red 48(Ca), C.I. Pigment Red 48(Mn), C.I. Pigment Red 57(Ca), C.I. Pigment Red 57:1, C.I. Pigment Red 112, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 168, C.I. Pigment Red 184, C.I. Pigment Red 202, and C.I. Pigment Violet 19.

Specific examples of the pigment which is used in the cyan ink include C.I. Pigment Blue 1, C.I. Pigment Blue 2, C.I. Pigment Blue 3, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 15:34, C.I. Pigment Blue 16, C.I. Pigment Blue 22, C.I. Pigment Blue 60, C.I. Vat Blue 4, and C.I. Vat Blue 60.

The liquid ink of the present invention may be applied to any substrate on which inkjet inks are typically applied, including porous materials. Upon application of ink droplets onto a porous substrate, the ink wets the substrate, the ink penetrates into the substrate, volatile components of the ink evaporate, leaving a dry mark on the substrate. Examples of porous substrates include paper, paperboard, cardboard, woven fabrics, and non-woven fabrics.

It is an unexpected result that the liquid ink of the present invention may be also successfully applied to non-porous substrates. Examples of non-porous substrates include glossy coated paper, glass, ceramics, polymeric substrate, and metal.

The liquid ink of the present invention is particularly suitable for use on polymeric substrates. Examples of polymeric substrates include polyolefin, polystyrene, polyvinyl chloride, nylon, polyethylene terephthalate, high-density polyethylene, low-density polyethylene, polypropylene, polyester, polyvinylidene chloride, urea-formaldehyde, polyamides, high impact polystyrene, polycarbonate, polyurethane, phenol formaldehyde, melamine formaldehyde, polyetheretherketone, polyetherimide, polylactic acid, polymethyl methacrylate, and polytetrafluoroethylene.

The liquid ink of the present invention is also suitable for use on metal substrates. Examples of metal substrates include base metals, ferrous metals, precious metals, noble metals, copper, aluminum, steel, zinc, tin, lead, and any alloys thereof. The liquid ink that is so applied onto the substrate, after evaporation of the solvent, results in a residue that adheres to the substrate.

The liquid ink of the present invention is also suitable for use of high surface energy substrates. Examples of high surface energy substrates include phenolic, nylon, alkyd enamel, polyester, epoxy, polyurethane, acrylonitrile butadiene styrene copolymer, polycarbonate, rigid polyvinyl chloride, and acrylic.

The liquid ink of the present invention is also suitable for use of low surface energy substrates. Examples of low surface energy substrates include polyvinyl alcohol, polystyrene, acetal, ethylene-vinyl acetate, polyethylene, polypropylene, polyvinyl fluoride, and polytetrafluoroethylene. Upon application to a low energy substrate, the volatizable components of the ink evaporate to yield a coating on the substrate. Such a coating is resistant to water or cleaning solvents.

Upon application of the liquid ink to the substrate, the volatile portions of the ink evaporate, leaving behind a residue or a coating on the substrate. The coating on the non-porous substrate is found on the surface of the substrate. The adhesion of the coating to the non-porous substrate is a crucial characteristic of the liquid ink. It surprising that the liquid ink of the present invention, wherein upon application to a polymeric substrate, a fabric or a metal substrate and evaporation of the volatizable components of the ink to yield a coating on the substrate, that the resulting coating is resistant to water or a cleaning solvent.

The cleaning solvent as used to clean such substrates are the typical household cleaners, such as general purpose cleaner, bathroom cleaner, disinfectant, scouring cleanser, glass cleaner, carpet or upholstery cleaner, spot or stain remover, and toilet bowl cleaner. Such cleaners comprise a wide variety of ingredients, including surfactants, builders, solvents, antimicrobials, and other additives.

Surfactants in the cleaning solvent include anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants. Examples of anionic surfactants include linear alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate, dodecylbenzene sulfonate, and sodium laurylbenzene sulfonate; alpha sulfo methyl ester, alpha sulfo acid ester, alkyl polyglucoside, alkyl polyglycoside, alcohol sulfate such as lauryl sulfate, alcohol ether sulfate such as lauryl ether sulfate and laureth sulfate, lauryl sarcosinate, and soap. Examples of nonionic surfactants include alcohol ethoxylate such as linear alcohol ethoxylate and primary alcohol ethoxylate, ethoxylated alcohol, alcohol polyethylene glycol ether, lauryl amine oxide, nonylphenol ethoxylate, octylphenol ethoxylate, and cocoamide diethanolamide. Examples of cationic surfactants include C₈ to C₁₂ dialkyl dimethyl ammonium chloride, alkyl dimethyl benzyl ammonium chloride, alkyl dimethyl ethylbenzyl ammonium chloride, hexadecyl trimethyl ammonium bromide, and quaternary ammonium chloride.

Builders include a range of both organic and inorganic chemicals whose function is to improve the performance of the surfactants. Builders are used to adjust or maintain the pH of the washing solution; soften water by removing calcium and other metal ions; and boost, reduce, or maintain foam height. Examples of builders include acetic acid, calcium carbonate, calcium chlorate, calcium chloride, calcium hydroxide, citric acid, diethanolamine, monoethanolamine, potassium hydroxide, potassium silicate, sodium metasilicate, potassium hydroxide, sodium bicarbonate, sodium bisulfate, sodium carbonate, sodium chloride, sodium citrate, sodium EDTA, sodium hydroxide, sodium sesquicarbonate, sodium silicate, sodium sulfate, sodium tripolyphosphate, tetrapotassium pyrophosphate, triethanolamine, and trisodium phosphate.

The cleaning solvent comprises one or more solvents, aside from water, which are added to help dissolve oil and grease. Examples of solvents in the cleaning solvent include acetone, almond oil, ammonia, ammonium hydroxide, apricot kernel oil, t-butyl alcohol, 1,2-butylene oxide, citronella oil, citrus oil (d-limonene, orange oil, lime oil), diethylene glycol monobutyl ether, 2,2-butoxyethoxy ethanol, butyl diglycol, dimethoxymethane, dipropylene glycol methyl ether, ethanol, ethylene glycol ethyl ether, ethylene glycol monobutyl ether, 2-butoxyethanol, eucalyptus oil, glycerine, 1,2,3-propanetriol, hexylene glycol, isopropanol, lavender oil, mineral oil, naphtha, peppermint oil, pine oil, pinene, propylene glycol, propylene glycol ether, propylene glycol methyl ether, 1-methoxy-2-propanol, rosemary oil, toluene, 1,1,1-trichloroethane, and xylene.

Antimicrobials are pesticides which kill bacteria, fungus, or mildew on surfaces. Examples of antimicrobials in the cleaning solvent include calcium hypochlorite, dialkyl dimethyl ammonium, octyl chloride, decyl chloride, didecyl chloride, alkyl dimethyl benzyl ammonium chloride, alkyl dimethyl ethylbenzyl ammonium chlorides, calcium hypochlorite, glutaraldehyde, o-benzyl-p-chloro phenol, o-phenyl phenol, sodium dichloro-s-triazinetrione, sodium hypochlorite, and sodium trichloro-s-triazinetrione.

The cleaning solvent may further comprise other ingredients, such as abrasives, fragrances, dyes, thickeners, hydrotopes, and preservatives. A hydrotope is a substance which keeps a cleaning solvent from separating. Examples of such ingredients include aloe vera, carbon dioxide, chalk, 1-(3-chloroallyl)-3,5,7-triaza-1-azoniaadamantane chloride, clay, denatonium benzoate, Bitrex, amylase enzyme, proteinase enzyme, extract of berberis, extract of marigold, feldspar, fluoraliphatic acid salt, hydrochloric acid, hydroxyacetic acid, isobutane, magnesium oxide, methylparaben, methyl salicylate, oxalic acid, o-benzyl-p-chlorophenol, phenylmethanol, phenylcarbinol, phosphoric acid, propane, propylparaben, silica, amorphous, silica, crystalline, sodium cumene sulfonate, sodium naphthalene sulfonate, sodium octane sulfonate, sodium perborate, borax, sodium xylene sulfonate, styrene maleic anhydride resin, sulfamic acid, urea, witch hazel, and xanthan gum.

Another aspect of the present invention is the method for preparing the hybridized copolymer which may be used for preparation of the liquid ink. There are three methods that can be used to prepare the hybridized copolymer: a three-part synthesis process, a two-part synthesis process, and a single part synthesis process.

In the three part synthesis process for preparing the hybridized copolymer, comprises the steps of

(a) reacting a functionalized hydrophobic polymer of an average molecular mass from about 15 to about 200 kilodaltons, with a hybridizing compound to create a reaction mixture;

(b) adding a first monomer component to the reaction mixture;

(c) adding a second monomer component to the reaction mixture; and

(d) neutralizing the reaction mixture with a base;

wherein the hydrophobic polymer is selected from the group consisting of a polysiloxane polymer, a polyolefin polymer, a polyvinyl polymer, and a copolymer thereof;

wherein either of the monomer components or both of the monomer components comprise a polymerizable unsaturated monomer; and

wherein either of the monomer components or both of the monomer components comprises a polymerizable acid-containing unsaturated monomer.

The preparation for the hybridized copolymer may add one or more additional steps before steps (a), (b), (c), and (d). The preparation for the hybridized copolymer may add one or more additional steps after steps (a), (b), (c), and (d). The preparation for the hybridized copolymer may add one or more additional steps between any of the steps (a), (b), (c), and (d). Such additional steps may include adding further reactants, adding a third or fourth or additional monomer components to the reaction mixture, changing the reaction conditions, working up the reaction mixture, and purifying any of reactants.

Further, any of the individual steps (a), (b), (c), and (d) may comprise additional necessary components or sub-steps in order to prepare the hybridized copolymer. For example, in addition to the two components mentioned in step (a), namely the functionalized hydrophobic polymer and the hybridizing compound, this step may also require additional components such as a solvent and a catalyst.

In step (a) of the three-part synthesis of the hybridized copolymer, the functionalized hydrophobic polymer is reacted with a hybridizing compound. The molecular weight of the functionalized hydrophobic polymer is selected such that the functionalized hydrophobic polymer is soluble in organic solvents used in the reaction, and that the resulting copolymer is water-based in the jet ink. The functionalized hydrophobic polymer has an average molecular weight in the range between 15,000 g/mol to 200,000 g/mol. Under one embodiment of the invention, the average molecular weight is in the range from 15,000 g/mol to 50,000 g/mol.

The reaction of the functionalized hydrophobic polymer with a hybridizing compound results a reaction mixture. The reaction mixture at the end of step (a) comprises the reaction product of the reaction of the functionalized hydrophobic polymer with a hybridizing compound, any compound that was added in excess, and other compounds, such as a solvent, or a catalyst.

The molar ratio of the functional groups on the functionalized hydrophobic polymer to the hybridizing compound is selected so that all, or nearly all, of the functional groups on the functionalized hydrophobic polymer are reacted with the hybridizing compound.

The functionalized hydrophobic polymer is a functionalized polysiloxane polymer, or a functionalized polyolefin polymer, or a functionalized polyvinyl polymer, or a copolymer of any of these three functionalized polymers. Under a preferred embodiment the functionalized hydrophobic polymer is a functionalized hydrophobic copolymer.

The functionalized polyolefin polymer is a polyolefin polymer that contains functional groups which are used to attach the side chains in further steps of the reaction. Polyolefin polymer is a polymer produced from one or more alkenes with a general formula C_(n)H_(2n), wherein n is 2 to 8. Such alkenes may be linear or branched. Examples of alkenes include ethylene, propylene, butylene, pentene, and hexene. Examples of suitable polyolefins include functionalized polyethylene, functionalized polypropylene, functionalized polybutene, functionalized polyisobutylene, functionalized polymethylpentene, and copolymers thereof.

Under one embodiment of the present application, the polyolefin that is used in preparation of the hybridized copolymer of the present application is a polyolefin that acts as an adhesion promoter to thermoplastic olefin and polypropylene. Such adhesion promoter may be either chlorinated or non-chlorinated. Under one embodiment the adhesion promoter is non-chlorinated. Examples of chlorinated polyolefins include chlorinated polypropylene, such as Superchlon 822S, 892LS, 930S, 803LS, 803MWS, 833S, and 814HS. It has been found that the non-chlorinated version of polyolefin may work better than the chlorinated version. Examples of non-chlorinated version of an adhesion promoter includes Eastman AP 550-1, Hardlen CY 9122P, Superchlon 892L.

The functionalized polyvinyl polymer is a polyvinyl polymer that contains functional groups that are used to attach the side chains in further steps of the reaction. Polyvinyl polymer is a polymer produced from one or more vinyl monomers. Examples of vinyl monomers include vinyl chloride, vinyl acetate, and maleic acid. Examples of suitable polyvinyl polymers include polyvinyl chloride, polyvinyl acetate, polymerized maleic acid, and copolymers thereof.

Particularly suitable polyvinyl polymers are copolymers of vinyl chloride, maleic acid and vinyl acetate. It is a surprising and unexpected result that one of the preferred polyvinyl vinyl polymers comprises copolymer based on about 60% to 95% vinyl chloride, 10% to 20% vinyl acetate, and about 1% maleic acid. Examples of suitable polyvinyl polymers include UCAR™ VMCC (a vinyl terpolymer comprising 83 wt % vinyl chloride and 16 wt % vinyl acetate, and 1 wt % maleic acid, mw 19 kDa, available from Dow Chemical Company) and Vinnol® H 15/45 M (a vinyl terpolymer comprising 84 wt % vinyl chloride and 15 wt % vinyl acetate, and 1 wt % dicarboxylic acid, available from Wacker Chemie AG).

The functionalized polysiloxane polymer is a polysiloxane polymer that has covalent bonds to other parts of the molecule, namely copolymeric side chains. Polysiloxane polymer is a linear polymer of formula [RR′SiO]_(n), wherein R and R′ are same or different organic groups such as hydrogen, alkyl, aryl, or alkylaryl. Such alkyl groups may be linear or branched. Examples of suitable functionalized polysiloxane polymer include functionalized polydimethylsiloxane, functionalized polymethylhydrosiloxane, functionalized poly(methylhydro-co-dimethyl)siloxane, functionalized polyethylhydrosiloxane, functionalized polyphenyl-(dimethylhydro)siloxane, functionalized methylhydrosiloxane-phenylmethylsiloxane copolymer, functionalized methylhydrosiloxane-octylmethylsiloxane copolymer, and co-polymers of any two or more thereof.

Although the functionalized hydrophobic polymer may comprise a homopolymer of functionalized polysiloxane units, or a homopolymer of functionalized polyolefin units, or a homopolymer of functionalized polyvinyl units, the functionalized hydrophobic polymer in the hybridized copolymer of the present invention may also be a copolymer of any of these three copolymers. It has been found that a particularly suitable functionalized hydrophobic polymer is the copolymer of a functionalized polyvinyl polymer and a functionalized polysiloxane polymer. Alternatively, the functionalized hydrophobic polymer may comprise a copolymer of a functionalized polyvinyl polymer and a functionalized polyolefin polymer. Furthermore, the functionalized hydrophobic polymer may comprise a copolymer of a functionalized polyvinyl polymer, a functionalized polysiloxane polymer, and a functionalized polyolefin polymer.

Under one embodiment the functionalized hydrophobic polymer comprises 5 to 60 weight percent of a functionalized polyvinyl polymer.

The functionalized hydrophobic polymer described above is reacted with a hybridizing compound. The hybridizing compound is a compound that reacts with at least one of the functionalized groups on the functionalized hydrophobic polymer, so that additional monomers may be added to the functionalized hydrophobic polymer via a polymerization reaction. The hybridizing compound reacts with the functional group of the functionalized hydrophobic polymer to yield a functionalized hydrophobic polymer substituted with a plurality of alkene groups (—CR═CH₂, wherein R is H or C₁ to C₃ alkyl group). Any of the alkene groups on the functionalized hydrophobic polymer is then capable of reacting readily with either a polymerizable unsaturated monomer or a polymerizable acid-containing unsaturated monomer via a polymerization reaction in step (b) of the three-parts synthesis.

The hybridizing compound comprises (1) a first functional group that is an alkene or is easily converted into an alkene, (2) a second functional group that is capable of reacting readily to the functional group of the functionalized hydrophobic polymer, to generate a bond between the former functionalized hydrophobic polymer and a portion of the former hybridizing compound, and (3) a divalent bridging group connecting the first functional group and the second functional group. It is important that after the reaction of the hybridizing compound and the functionalized hydrophobic polymer, that the resulting polymer comprises a plurality of alkene groups or are easily converted into alkene groups.

The hybridizing compound has a formula

R^(h1)—B¹—B²—B³—R^(h2),

wherein R^(h1)— is the first functional group on the hybridizing compound, —R^(h2) is the second functional group on the hybridizing compound. The assembly —B¹—B²—B³— represents the divalent bridging group connecting the first functional group to the second functional group, wherein any of —B¹—, —B²—, and —B³—, are each independently a bond, an ether group, an alkyl bridging group, a cycloalkyl bridging group or an aryl bridging group.

The alkyl bridging group may be further substituted with one or more of the following: a terminal alkyl, a terminal cycloalkyl or a terminal aryl group. The cycloalkyl bridging group may be further substituted with one or more of the following: a terminal alkyl, a terminal cycloalkyl or a terminal aryl group. The aryl bridging group may be further substituted with one or more of the following: a terminal alkyl, a terminal cycloalkyl or a terminal aryl group.

The first functional group on the hybridizing compound is any alkene group that is capable of further polymerization with a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer. Examples of such alkene groups include vinyl, allyl, isopropenyl, 1-methylvinyl, —CH═CH₂, —CH₂—CH═CH₂, —CH₂—CMe=CH₂, and —CH═CH—CH₃. The first functional group on the hybridizing compound is also an alkene precursor that may be reacted to yield an alkene group. Alkenes may be prepared by any known method, as long as the alkene preparative reaction does not react with other portions of the polymer. Examples of preparation of alkenes include alkyne reduction and beta-elimination reactions such as dehydration of alcohols, dehydrohalogenation of alkyl halides, and vicinal dihalide dehaloganation.

The second functional group on the hybridizing compound is a group that is reactive towards the functional group on the functionalized hydrophobic polymer, to generate a bonding group between the functionalized hydrophobic polymer and a portion of the former hybridizing compound. Examples of suitable second functional groups include an isocyanate, an amino, an epoxy, a hydroxy, a carboxylic acid and an acyl halide.

The bonding group is a divalent group spanning the functional hydrophobic polymer and the portion of the former hybridizing compound. When the functional group on the functionalized hydrophobic polymer is a hydroxyl group, then the bonding group may be an ester linkage, an ether linkage, or a carbamate linkage.

When the functional group on the functionalized hydrophobic polymer is a hydroxy group, and the second functional group on the hybridizing compound is a carboxylic acid, then under appropriate reaction conditions the ester linkage is formed.

When the functional group on the functionalized hydrophobic polymer is a hydroxy group, and the second functional group on the hybridizing compound is an acyl halide group, then under appropriate reaction conditions the ester linkage is formed.

When the functional group on the functionalized hydrophobic polymer is a hydroxy group, and the second functional group on the hybridizing compound is a second hydroxy group, then under appropriate reaction conditions the ester linkage is formed. Such conditions may include dehydration under acidic conditions.

When the functional group on the functionalized hydrophobic polymer is a hydroxy group, and the second functional group on the hybridizing compound is an isocyanate group, then under appropriate reaction conditions the carbamate linkage is formed. Examples of hybridizing compounds include 3-isopropenyl-α,α-dimethylbenzyl isocyanate, CH₂═CMe-C₆H₄—CMe₂-NCO, and isocyanatoethyl methacrylate.

When the functional group on the functionalized hydrophobic polymer is a carboxylic acid group, and the second functional group on the hybridizing compound is an epoxy group, then under appropriate reaction conditions the ester linkage is formed. The hybridizing compound may be an aromatic epoxide, alicyclic epoxide, or an aliphatic epoxide.

An example of a hybridizing compound wherein the second functional group is an epoxy group is allyl glycidyl ether.

The number of side chains on the backbone is largely controlled by the number of functional groups on the functionalized hydrophobic polymer; because each of the functional groups is potentially an attachment point for a side chain, the higher the number of functional groups on the functionalized hydrophobic polymer, the higher the number of side chains per molecule of functionalized hydrophobic polymer that may be potentially be bound to the backbone. In order to take an advantage of a functional group on the functionalized hydrophobic polymer to act as an attachment site for a side chain, the functional group must react with a hybridizing compound.

In order to achieve full substitution, wherein essentially all of the functional groups that can be readily reacted are to act as an attachment site for a side chain, a molar ratio of the hybridizing compound to the functional group on the functionalized hydrophobic polymer is 1:1 or slightly higher. This ratio may be in the range 1:1 to 1.3:1. The slight molar excess of the hybridizing compound may be needed to achieve a full substitution. However, molar excess that is too high is not desirable, because high levels of unreacted hybridizing compound may cause undesirable side reactions.

In cases where it is desirable to have a lower number of side chains on the backbone, a functionalized hydrophobic polymer with a lower number of functional groups should be selected. In cases where it is desirable to have a high number of side chains on the backbone, a functionalized hydrophobic polymer with a higher number of functional groups should be selected.

Alternatively, it is possible regulate the number of side chains for any given backbone by adjusting the molar ratio of the hybridizing compound to the functional group on the functionalized hydrophobic polymer. The molar ratio in the range from more than 0:1 to less than 1:1 yields a hybridized copolymer wherein only a portion of the functional groups have been replaced with a side chain. For example, if the molar ratio of first monomer component to the functional groups on the functionalized hydrophobic polymer is 0.5:1, then only about half the functional groups will be replaced with a side chain.

The reaction of the functionalized hydrophobic polymer with the hybridizing compound in step (a) of the three-part synthesis of the hybridized copolymer may take place neat, i.e., without any other compounds present. Under a different embodiment this reaction takes place in presence of additional materials, such as solvents, catalysts and initiators.

The solvent for step (a) of the synthesis of the hybridized copolymer, the reaction of the functionalized hydrophobic polymer with the hybridizing compound, is a solvent which dissolves or disperses both the functionalized hydrophobic polymer and the hybridizing compound. Any commonly used solvent is appropriate, as long as the functionalized hydrophobic polymer, the hybridizing compound, the reaction product of the reaction of functionalized hydrophobic polymer with a hybridizing compound, the first monomer component, and the second monomer components are soluble or dispersable within the solvent and they do not react with the solvent. Suitable solvents or diluents for step (a) of the above reaction are an inert organic liquid. Examples of such a solvent includes mineral oil; straight and branched-chain hydrocarbons, such as pentane, isopentane, hexane, isohexane, heptane, octane, dodecane, and mixtures thereof; cyclic and alicyclic hydrocarbons, such as cyclohexane, cycloheptane, methylcyclohexane, methylcycloheptane, and mixtures thereof; halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride, perfluorinated C₅ to C₁₀ alkanes; chlorobenzenes; aromatic and alkylsubstituted aromatic compounds, such as benzene, toluene, mesitylene, and xylene; ethers, such as diethyl ether, tetrahydrofuran; ketones, such as acetone, methyl ethyl ketone; dimethyl sulfoxide; and acetonitrile.

In addition to the inert organic liquids, labile solvents may be used during the preparation of the hybridized copolymer, if added in an appropriate sequence. Examples of these solvents include alcohols, such as butanol, isopropanol, n-propanol, ethanol, and methanol.

The catalyst added to the mixture in step (a) of the preparation of the hybridized copolymer is any compound which helps with controlling or advancing the reaction of the hybridizing compound with the functionalized hydrophobic polymer. In another embodiment, the catalyst added to the mixture in step (a) of the preparation of the hybridized copolymer is an additive that catalyzes further reaction of the resulting compound with a polymerizable unsaturated monomer, or a polymerizable acid-containing unsaturated monomer, or both.

The reaction of the functionalized hydrophobic polymer with a hybridizing compound results in a reaction mixture, which can then be reacted further. Step (b) follows step (a), either immediately, after some intermediate steps that follow step (a) and precede step (b).

In step (b), the first monomer component is added to the reaction mixture. Upon addition of the first monomer component, the monomers comprising the first monomer component react with the reaction product of functionalized hydrophobic polymer and hybridizing compound, to create a hybridized copolymer intermediate. The first monomer component upon exposure to the reaction mixture reacts with the alkene groups on the functionalized hydrophobic polymer that has been reacted with the hybridizing compound, wherein the alkene corresponds to the first functional group on the hybridizing compound.

The molar ratio of the monomers of the first monomer component to the alkene groups on the functionalized hydrophobic polymer determines the length of the copolymeric side chains on the hybridized copolymer intermediate. For example, for a molar ratio of 10:1, the average length of the side chain on the hybridized copolymer intermediate will be 10 units.

The first monomer component comprises either a polymerizable unsaturated monomer or a polymerizable acid-containing unsaturated monomer or a mixture thereof. The first monomer component may comprise a polymerizable unsaturated monomer. The first monomer component comprises a polymerizable acid-containing unsaturated monomer. The first monomer component may comprise a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer. The first monomer component may comprise a plurality of polymerizable unsaturated monomers. The first monomer component may comprise a plurality of polymerizable acid-containing unsaturated monomers. The first monomer may comprise a plurality of polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer. The first monomer component may comprise a polymerizable unsaturated monomer and a plurality of polymerizable acid-containing unsaturated monomers. The first monomer component may comprise a plurality of polymerizable unsaturated monomers and a plurality of polymerizable acid-containing unsaturated monomers.

The first monomer component may comprise only one or more monomers. Additionally, the first monomer component may comprise additional additives. Examples of such additives include a solvent, a diluent, a catalyst, an initiator, a hybridizing compound, chain transfer agent and a UV absorber. A description of possible solvents, catalysts, initiators, hybridizing compounds, and UV absorbers is presented further below.

The reaction of the first monomer component with the reaction product of the reaction of the functionalized hydrophobic polymer with the hybridizing compound produces the hybridized copolymer intermediate. The hybridized copolymer intermediate has a backbone and a plurality of side chains. The side chains are the product of the polymerization reaction of the monomers of the first monomer component. The hybridized copolymer intermediate differs from the hybridized copolymer in that the hybridized copolymer intermediate has shorter side chains. The side chains are extended by reacting the hybridized copolymer intermediate with the second monomer mixture, wherein the monomers of the second monomer mixture polymerize to extend the side chains.

The hybridized copolymer intermediate is then reacted further with the second monomer component. Step (c) follows step (b), either immediately, after some intermediate steps that follow step (b) and precede step (c).

In step (c), the second monomer component is added to the reaction mixture. Upon addition of the second monomer component, the monomers comprising the second monomer component react with the hybridized copolymer intermediate to create a pre-neutralized hybridized copolymer. The monomers comprising the first monomer component upon exposure to the hybridized copolymer intermediate polymerize with the polymerized monomers of the first monomer component, thus extending the side chains.

The molar ratio of the monomers of the second monomer component to the existing side chains determines the extension of the copolymeric side chains. For example, for a molar ratio of 10:1, the average length of the extension of the side chain will be 10 units.

The second monomer component comprises either a polymerizable unsaturated monomer or a polymerizable acid-containing unsaturated monomer or a mixture thereof. The second monomer component may comprise a polymerizable unsaturated monomer. The second monomer component comprises a polymerizable acid-containing unsaturated monomer. The second monomer component may comprise a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer. The second monomer component may comprise a plurality of polymerizable unsaturated monomers. The second monomer component may comprise a plurality of polymerizable acid-containing unsaturated monomers. The second monomer may comprise a plurality of polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer. The second monomer component may comprise a polymerizable unsaturated monomer and a plurality of polymerizable acid-containing unsaturated monomers. The second monomer component may comprise a plurality of polymerizable unsaturated monomers and a plurality of polymerizable acid-containing unsaturated monomers.

The second monomer component may comprise only one or more monomers. Additionally, the second monomer component may comprise an additional additive. Examples of such an additive include a solvent, a diluent, a catalyst, an initiator, a hybridizing compound, a chain transfer agent, and a UV absorber.

The first monomer component or the second monomer component, or both, may comprise a solvent or a diluent. The solvent or the diluent for step (b) or (c) of the synthesis of the hybridized copolymer is a solvent which dissolves or disperses other materials in the first monomer component, such as a polymerizable unsaturated monomer or a polymerizable acid-containing unsaturated monomer. Any commonly used solvent or diluent is appropriate, as long as the reaction product of the reaction of the functionalized hydrophobic polymer with the hybridizing compound, the first monomer component, and the second monomer component are soluble or dispersable within the solvent and they do not react with the solvent. Suitable solvents or diluents for step (b) or (c) of the above reaction is an inert organic liquid. Examples of such a solvent includes mineral oil; straight and branched-chain hydrocarbons, such as pentane, isopentane, hexane, isohexane, heptane, octane, dodecane, and mixtures thereof; cyclic and alicyclic hydrocarbons, such as cyclohexane, cycloheptane, methylcyclohexane, methylcycloheptane, and mixtures thereof; halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride, perfluorinated C₅ to C₁₀ alkanes; chlorobenzenes; aromatic and alkylsubstituted aromatic compounds, such as benzene, toluene, mesitylene, and xylene; ethers, such as diethyl ether, tetrahydrofuran; ketones, such as acetone, methyl ethyl ketone; dimethyl sulfoxide; acetonitrile. In addition to the inert organic liquids, labile solvents may be used during the preparation of the hybridized copolymer, if added in an appropriate sequence. Care must be taken not to use such labile solvents that may interfere with the polymerization reaction of the side chains after the addition of the first and second monomer component.

The first monomer component or the second monomer component, or both components, may comprise a catalyst or an initiator. The catalyst or initiator added to the mixture in steps (b) or (c) of the preparation of the hybridized copolymer is any compound which helps with controlling or advancing the polymerization of the polymerizable unsaturated monomer or a polymerizable acid-containing unsaturated monomer or both, with the reaction product of the reaction of the functionalized hydrophobic polymer with the hybridizing compound, regardless if the polymerizable unsaturated monomer or a polymerizable acid-containing unsaturated monomer is added to the reaction mixture in step (b) or step (c) or any other step. The initiator component may be added to the reaction mixture simultaneous with either the first monomer component, or the second monomer component, or both. Under one embodiment of the invention of the present invention, the initiator component comprises a free radical polymerization initiator.

Examples of such catalysts and initiators include metal catalysts, such as dibutyltin dilaurate, diisobutyryl peroxide, cumyl peroxyneodecanoate, di(3-methoxybutyl)peroxydecarbonate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, cumyl peroxyneoheptanoate, tert-amyl peroxyneodecanoate, di-sec-buyl peroxydicarbonate, diisopropyl peroxydicarbonate, di(4-t-butylcyclohexyl)peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, dibutyl peroxydicarbonate, tert-butyl-peroxyneodecanoate, dicetyl peroxydicarbonate, dimyristyl peroxydicarbonate, 1,1,3,3-tetramethylbutyl peroxypivalate, tert-butyl peroxyneoheptanoate, tert-amyl peroxypivalate, tert-butyl peroxypivalate, di(3,5,5-trimethylhexanoyl) peroxide, dilauroyl peroxide, didecanoyl peroxide, 2,2′-azodi(isobutyronitrile), Perkodox AMBN, 2,2′-azodi(2-methylbutonitrile), 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, dibenzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxydiethylacetate, tert-butyl peroxyisobutyrate, 1,1′-azodi(hexahydrobenzonitrile), 1,1-ditert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-di(tert-amylperoxy)cyclohexane, 1,1-di(tert-butylperoxy)cyclohexane, tert-amylperoxy-2-ethylhexyl carbonate, tert-amyl peroxyacetate, tert-butyl peroxu-3,5,5-trimethylhexanoate, 2,2-di(tert-butylperoxy)butane, tert-butylperoxy isopropyl carbonate, tert-butylperoxy-2-ethylhexylcarbonate, tert-amyl peroxybenzoate, tert-butyl peroxyacetate, butyl 4,4-di(tert-butylperoxy)valerate, tert-butyl peroxybenzoate, dicumyl peroxide, di(tert-butylperoxyisopropyl)benzene, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, tert-butyl cumyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hex-3-yne, di-tert-butyl peroxide, 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxonane, isopropylcumyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, 3,3,5,7,7-pentamethyl-1,2,4-trioepane, cumyl hydroperoxide, tert-butyl hydroperoxide, tert-amyl hydroperoxide, and 2,3-dimethyl-2,3-diphenylbutane, tert-amyl peroxybenzoate, 4,4-azobis(4-cyanovaleric acid), 1,1′-azobis(cyclohexanecarbonitrile), 2,2′-azobisisobutyronitrile (AIBN), benzoyl peroxide, 2,2-bis(tert-butylperoxy)butane, 1,1-bis(tert-butylperoxy)cyclohexane, 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane, 2,5-bis(tert-butylperoxy)-2,5-dimethyl-3-hexyne, bis(1-(tert-butylperoxy)-methylethyl)benzene, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl hydroperoxide, tert-butyl peracetate, tert-butyl peroxide, tert-butyl peroxybenzoate, tert-butylperoxy isopropyl carbonate, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, lauroyl peroxide, 2,4-pentanedione peroxide, peracetic acid, and potassium persulfate.

The polymerization may also be carried out in the presence of a conventionally known chain transfer agent, or a mixture of chain transfer agents. The chain transfer agent may be added to the reaction mixture with any of the monomer components, before the addition of a monomer component, or after a monomer component. Examples of chain transfer agents include mercaptans, such as octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan, and t-tetradecyl mercaptan; xanthogen disulfides, such as dimethyl xanthogen disulfide, diethyl xanthogen disulfide, and diisopropyl xanthogen disulfide; thiuram disulfides, such as tetramethyl thiuram disulfide, tetraethyl thiuram disulfide, and tetrabutyl thiuram disulfide; halogenated hydrocarbons, such as carbon tetrachloride and ethylene bromide; selected hydrocarbons, such as pentaphenylethane, 1,1-diphenylethylene, and alpha-methylstyrene dimer; unsaturated heterocyclic compounds, such as xanthene, 2,5-dihydrofuran, 9,10-dihydroanthracene, 1,4-dihydronaphthalene, indene, and 1,4-cyclohexadiene; and other chain transfer agents such as acrolein, methacrolein, 2-ethylhexylthioglycolate, terpinolene, alpha-terpinene, gamma-terpinene, and dipentene. The preferred chain transfer agents are mercaptans. The amount of the chain transfer agent added is 0.2 to 7 parts by weight, more preferably 0.2 to 5 parts by weight, particularly preferably 0.3 to 3 parts by weight, based on 100 parts by weight in total of the polymerizable unsaturated monomer and polymerizable acid-containing unsaturated monomer.

The first monomer component or the second monomer component, or both components, may comprise a hybridizing compound. The hybridizing compound that may be has a formula

R^(h1)—B¹—B²—B³—R^(h2),

wherein R^(h1)— is the first functional group on the hybridizing compound, —R^(h)2 is the second functional group on the hybridizing compound. The assembly —B¹—B²—B³— represents the divalent bridging group connecting the first functional group to the second functional group, wherein any of —B¹—, —B²—, and —B³—, are each independently a bond, an alkyl bridging group, a cycloalkyl bridging group or an aryl bridging group. Each of these moieties is described more fully above. The hybridizing compound that is a part of the first monomer component or the second monomer component may the same or different than the hybridizing compound selected for use in step (a).

The first monomer component or the second monomer component, or both components, may comprise a UV absorber. Such a UV absorber may be added to the first monomer component or the second monomer component, or both components, to improve the physical or chemical properties of the hybridized copolymer, such as the stability of the ink. Such a UV absorber will dissipate the energy that is absorbed by the printed ink thus mitigating the aging process of the printed ink. Such a UV absorber will absorb the UV radiation and prevent the formation of free radicals. Examples of UV absorbers that may be incorporated into the side chains include benzophenones, hindered amine light stabilizers, benzotriazoles, nickel quenchers, 2-(2′-hydroxy-5′-methacryloyloxy ethylphenyl)-2-H-benzotriazole, Ruva 93, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate and methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate.

The reaction of the second monomer component with the hybridized copolymer intermediate results in the pre-neutralized hybrid copolymer. Although the neutralization step (d) may follow step (c) immediately, there may be one or more intermediate steps that follow step (c) and precede step (d). Such steps may include one or more additions of a polymerization initiator, a solvent, an antioxidant, a catalyst, or any mixture thereof. Such steps may also include partial evaporation of the solvent.

The reaction of the second monomer component with the hybridized copolymer intermediate results in the pre-neutralized hybrid copolymer. In step (d), the pre-neutralized hybrid copolymer is then neutralized with an acid.

The neutralization of the pre-neutralized hybrid copolymer completes the formation of the hybrid copolymer. The hybrid copolymer may then be precipitated, or washed, or isolated, or further used in the preparation of a liquid ink.

The base which is used to neutralize the pre-neutralized hybrid copolymer should strong enough to cause neutralization to occur, but it should not be strong enough to degrade the pre-neutralized hybrid copolymer. The base is preferably a weak base. Examples of suitable bases include secondary amines and tertiary amines. The secondary amine is a compound comprising the group R—NH—R, wherein moieties R are each aliphatic groups which may or may not be the same. The tertiary amine is a compound comprising the group R₃N, wherein moieties R are aliphatic groups which may or may not be the same as the other groups.

An example of a suitable weak base includes dimethylethanolamine. In one embodiment the acid is a mixture of two or more acids.

Following step (d) of the synthesis of the hybridized copolymer of the present invention, additional steps may be needed to obtain the hybridized copolymer. Such steps may include an addition of a solvent, a diluent, a polymerization initiator, a catalyst, or any mixture thereof. Such steps may also include partial evaporation of the solvent.

In the preparation of the hybridized copolymer, either of the monomer components or both of the monomer components comprise a polymerizable unsaturated monomer. Under one embodiment of the present invention, the polymerizable unsaturated monomer is found within the first monomer component. Under another embodiment of the present invention, a plurality of the polymerizable unsaturated monomer is found within the first monomer component. Under another embodiment of the present invention, the polymerizable unsaturated monomer is found within the second monomer component. Under another embodiment of the present invention, a plurality of the polymerizable unsaturated monomer is found within the second monomer component. Under another embodiment of the present invention, the polymerizable unsaturated monomer is found within the first monomer component and within the second monomer component.

The polymerizable unsaturated monomer is selected from a group consisting of an acrylate monomer, an alkacrylate monomer, an aromatic vinyl monomer, an aliphatic vinyl monomer, a vinyl ester monomer, a vinyl cyanogen-containing monomer, a halogenoid monomer, an olefin monomer, a diene monomer, and a carboxylic acid-containing monomer. Although only one kind of a polymerizable unsaturated monomer may be used in preparation, under another embodiment a plurality of polymerizable unsaturated monomers may be used.

The polymerizable unsaturated monomer that is the basis of one type of repeating units within the side chain of hybrid copolymer has the formula

CH₂═C(R²)—X—Y—R¹,  (Formula 1)

wherein

—R² is H, halogen, or C₁ to C₃ alkyl group;

—X— is a bond, —CO—O—, or —O—CO—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H, a halogen, —OH, or —CN;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

A halogen is an atom of the 17th Group of the periodic table, which includes fluorine, chlorine, bromine and iodine.

C₁ to C₃ alkyl group is a methyl group, ethyl group, n-propyl group, or a i-propyl group.

C₁ to C₂₂ bridging alkyl group is a saturated bridging group of formula —(CH₂)_(n)— wherein n is an integer 1 to 22. The term “alkyl” as used to refer to a bridging group, a divalent group, is referred under current IUPAC rules as “alkdiyl” group. This bridging group may be further substituted anywhere along the chain by a small terminal alkyl group such as methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomer any of the foregoing.

In cases when —X— is a bond, the formula CH₂═C(R²)—X—Y—R¹, is reduced to formula CH₂═C(R²)—Y—R¹. Likewise, when —Y— is a bond, the formula CH₂═C(R²)—X—Y—R¹, is reduced to formula CH₂═C(R²)—Y—R¹. Furthermore, when both —X— and —Y— are bonds, the formula CH₂═C(R²)—X—Y—R¹, is reduced to CH₂═C(R²)—R¹.

The symbol —CN refers to a cyanyl group. The cyanyl group should be chemically inert vis-à-vis conditions in which the copolymer may be exposed in order to avoid hydrolysis of the cyanyl group.

Under one embodiment of the present invention, the polymerizable unsaturated monomer which is the basis for the side chains is an acrylate monomer, an alkacrylate monomer, or both. The acrylate monomer is of formula

CH₂═C(R²)—X—Y—R¹,

wherein

—R² is H;

—X— is —CO—O—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H or —OH;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy; or

(6) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe.

The acrylate monomer is also of formula

CH₂═CH—CO—O—Y—R¹,

wherein

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H or —OH;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy; or

(6) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe.

Examples of suitable acrylate are 2-hydroxyethyl acrylate, HEA, ethyl acrylate, methyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, n-pentyl acrylate, n-amyl acrylate, i-pentyl acrylate, isoamyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, i-octyl acrylate, decyl acrylate, isodecyl acrylate, dodecyl acrylate, lauryl acrylate, octadecyl acrylate, isobornyl acrylate, phenyl acrylate, benzyl acrylate, ethylene glycol methyl ether acrylate, glycidyl acrylate, and mixtures thereof. Under one embodiment of the invention the acrylate monomers that are the basis of the copolymeric side chain is 2-hydroxylethyl acrylate, ethyl acrylate, or a mixture thereof.

The alkylacrylates monomer is of formula

CH₂═C(R²)—X—Y—R¹,

wherein

—R² is C₁ to C₃ alkyl;

—X— is —CO—O—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with OH or OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

One example of an alkylacrylate monomer is a methacrylate. The methacrylate has a formula

CH₂═C(R²)—X—Y—R¹,

wherein

—R² is C₁ alkyl;

—X— is —CO—O—;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with OH or OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

C₁ alkyl is a methyl group.

Examples of suitable methacrylates include methyl methacrylate, MMA, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, s-butyl methacrylate, t-butyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, behenyl methacrylate, lauryl methacrylate, isobornyl methacrylate (IBOMA), phenyl methacrylate, benzyl methacrylate, 1-naphthyl methacrylate, (trimethylsilyl)methacrylate, 9-anthracenylmethyl methacrylate, glycidyl methacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, and ethylene glycol propylene glycol monomethacrylate. Under one embodiment of the invention the methacrylate monomers that are the basis of the copolymeric side chain is methyl 2-methacrylate, behenyl methacrylate, or a mixture thereof.

The aromatic vinyl monomer is of formula CH₂═C(R²)—R¹,

wherein

—R² is H or C₁ to C₃ alkyl group;

—R¹ is a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy.

An aryl group is any hydrocarbon cyclic group that follows the Hackel Rule. Such an aryl group may be a single aromatic ring group, a bicyclic aromatic ring group, or a tricyclic aromatic ring group. An example of a single aromatic ring group is the phenyl group. An example of a bicyclic aromatic ring group is naphthalene. An example of a tricyclic aromatic ring group is anthracene. Any of the aromatic groups may be optionally substituted with one or more of any of the following: fluorine, chlorine, bromine, iodine, methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propyloxy, including any isomers thereof.

Examples of suitable aromatic vinyl monomer include styrene, alpha-methylstyrene, vinyl toluene, 4-t-butylstyrene, chlorostyrene, vinylanisole, and vinyl naphthalene.

The vinyl ester monomer is of formula

CH₂═CH—O—CO—Y—R¹,

wherein

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is

(1) H, halogen, —OH, or —CN;

(2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group;

(3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen;

(4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes;

(5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy;

(6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group;

(7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe; or

(8) —CZ═CH₂, wherein Z is H or halogen.

An example of a suitable vinyl ester is vinyl acetate.

The vinyl cyanogen-containing monomer is an unsaturated monomer of Formula 1 that comprises a —CN group. Examples of cyanogen-containing monomer include acrylonitrile and methacrylonitrile.

The halogenoid monomer is an unsaturated monomer of Formula 1 that comprises one or more halogens. Examples of a halogen includes fluorine, chlorine, bromine and iodine. An example of a halogenoid comprising one halogen is vinyl chloride. An example of a halogenoid comprising two halogens is vinylidene chloride.

The olefin monomer is of formula

CH₂═C(R²)—Y—R¹,

wherein

—R² is H, or C₁ to C₃ alkyl group;

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R¹ is H.

Examples of an olefin monomer include ethylene and propylene.

The diene monomer is of formula

CH₂═CH—Y—CZ═CH₂,

wherein

—Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

Z is H or halogen.

An example of a diene monomer when Z═H is butadiene. An example of a diene monomer when Z is a halogen is chloroprene.

The polymerizable acid-containing unsaturated monomer which is the basis for one type of a building unit of the side chains is selected from a group consisting of an acid-containing acrylate, an acid-containing methacrylate, an acid-containing vinyl monomer, an acid-containing alkylallyl monomer, a monocarboxylic acid-containing alkene, a dicarboxylic acid-containing alkene, a salt of any of the preceding, and an ester of any of the preceding. Although only one kind of a polymerizable acid-containing unsaturated monomer may be used in preparation of any of the side chains, typically a several kinds of polymerizable acid-containing unsaturated monomers are used.

The acid-containing acrylate is any acrylate monomer that has an acid group on the same molecule. Examples of acid-containing acrylates include acrylic acid, a carboxylalkyl acrylate, a sulfoalkyl acrylate, and an alkene glycol acrylate phosphate.

The carboxylalkyl acrylate is any acrylate monomer that has a carboxylic acid group on the same molecule. The term “carboxyl acid group” means —C(O)—OH. Examples of carboxylalkyl acrylates include 2-carboxyethyl acrylate, carboxylmethyl acrylate, 3-carboxylpropyl acrylate, and 4-carboxybutyl acrylate.

The sulfoalkyl acrylate is any acrylate monomer that has a sulfoalkyl acid group on the same molecule. The term “sulfoalkyl acid group” means an alkyl group that comprises a —SO₃H group. Examples of sulfoalkyl acrylates include 2-sulfoethyl acrylate, sulfomethyl acrylate, 3-sulfopropyl acrylate, and 4-sulfobutyl acrylate.

The alkene glycol acrylate phosphate is any acrylate monomer that has a phosphoric acid group on the same molecule. The term “phosphoric acid group” means an alkyl group that comprises a phosphate group, or —OP(O)(OH)₂ group. Examples of alkene glycol acrylate phosphate include ethylene glycol acrylate phosphate, propylene glycol acrylate phosphate, and butylene glycol acrylate phosphate.

The acid-containing methacrylate is any methacrylate monomer that has an acid group on the same molecule. Examples of an acid-containing methacrylate include methacrylic acid, a carboxylalkyl methacrylate, a sulfoalkyl methacrylate, and an alkene glycol methacrylate phosphate.

The carboxylalkyl methacrylate is any methacrylate monomer that has a carboxylic acid group on the same molecule. The term “carboxyl acid group” means —C(O)—OH. Examples of carboxylalkyl methacrylates include 2-carboxyethyl methacrylate, carboxylmethyl methacrylate, 3-carboxylpropyl methacrylate, and 4-carboxybutyl methacrylate.

The sulfoalkyl methacrylate is any methacrylate monomer that has a sulfoalkyl acid group on the same molecule. The term “sulfoalkyl acid group” means an alkyl group that comprises a —SO₃H group. Examples of sulfoalkyl methacrylates include 2-sulfoethyl methacrylate, sulfomethyl methacrylate, 3-sulfopropyl methacrylate, and 4-sulfobutyl methacrylate.

The alkene glycol methacrylate phosphate is any methacrylate monomer that has a phosphoric acid group on the same molecule. The term “phosphoric acid group” means an alkyl group that comprises a phosphate group, or —OP(O)(OH)₂ group. Examples of an alkene glycol methacrylate phosphate include ethylene glycol methacrylate phosphate, propylene glycol methacrylate phosphate, and butylene glycol methacrylate phosphate.

The acid-containing vinyl monomer is any molecule that has a vinyl group —CH═CH₂, and an acid group. The acid group may be a carboxylic group, a sulfonic acid group or a phosphoric acid group. Examples of acid-containing vinyl monomers include 4-vinylbenzoic acid, 4-styrenesulfonic acid, 1-vinyl-1H-pyrrole-2-carboxylic acid, 4-ethyl-5-phenyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-(4-methoxyphenyl)-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-p-tolyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 2-vinyl-1,1-cyclopropanedicarboxylic acid, 2-isopropyl-6-methyl-3-vinyl-6-heptenoic acid, and vinyl sulfonic acid.

The acid-containing alkylallyl monomer is any alkylallyl monomer that has an acid group on the same molecule. The term alkylallyl refers to CH₂═C(R^(o2))—, wherein R^(o2) is an alkyl group. Examples of acid-containing alkylallyl monomers include methylallyl sulfonic acid.

The monocarboxylic acid-containing alkene is a molecule that contains an aliphatic carbon-carbon double bond, and also a single carboxylic acid group. The aliphatic carbon-carbon double bond can be at the end, or anywhere else in the molecule. In order to be useful for the preparation of the hybridized copolymer, the double bond must be polymerizable. Examples of monocarboxylic acid-containing alkene include crotonic acid, isocrotonic acid, and cinnamic acid.

The dicarboxylic acid-containing alkene is a molecule that contains an aliphatic carbon-carbon double bond, and also two carboxylic acid groups. The aliphatic carbon-carbon double bond can be at the end, or anywhere else in the molecule. With respect to the aliphatic carbon-carbon double bond, the carboxylic acid groups be on parts of molecules that are cis, trans, or gem to each other. In order to be useful for the preparation of the hybridized copolymer, the double bond must be polymerizable. Examples of dicarboxylic acid-containing alkenes include fumaric acid, itaconic acid, mesaconic acid, citraconic acid, and maleic acid.

The definition of polymerizable acid-containing unsaturated monomer also includes a salt of any of the preceding, and an ester of any of the preceding. The term “salt” refers to the complex that is made by replacing the acidic proton with a cationic moiety in the polymerizable acid-containing unsaturated monomer of any of the foregoing definitions. The term “ester” of any of the preceding refers to the molecule made by replacing the acidic proton with an alkyl group in the polymerizable acid-containing unsaturated monomer of any of the foregoing definitions.

The polymerizable acid-containing unsaturated monomer that is the basis of one type of repeating units within the side chain of hybrid copolymer under one embodiment has the formula

R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m),

wherein

R^(o4)— is H, C₁ to C₃ alkyl group, or an aryl group;

—R^(o2) is H, halogen, or C₁ to C₃ alkyl group;

—X^(o)— is a bond, or —CO—O—;

—Y^(o)— is a bond, or a C₁ to C₁ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups;

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding; and

m=1 or 2.

C₁ to C₃ alkyl group is a methyl group, ethyl group, n-propyl group, or an i-propyl group.

C₁ to C₁₈ bridging alkyl group is a saturated bridging group of formula —(CH₂)_(n)— wherein n is an integer 1 to 18. The term “alkyl” as used when referring to a bridging group, is a divalent group based on an alkane, and is referred to under current IUPAC rules as “alkdiyl” group. This bridging group may be further substituted anywhere along the chain by a small terminal alkyl group such as methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomer any of the foregoing.

The term “cycloalkyl” refers to an optionally substituted monocyclic, bicyclic or tricyclic hydrocarbon group of three to twelve carbon atoms, which may contain one or more carbon-carbon double bonds, or may be substituted by one or more substituents, such as alkyl, halo, oxo, hydroxy, alkoxy, alkanoyl, acylamino, carbamoyl, cyano, and like.

In cases when —X^(n)— is a bond, the formula R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R)_(m), is reduced to formula R^(o4)—CH═C(R²)—Y^(o)—(R^(o1))_(m). Likewise, when —Y^(n)— is a bond, the formula R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m), is reduced to formula R^(o4)—CH═C(R^(o2))—X^(o)—(R^(o1))_(m). Furthermore, when both —X^(n)— and —Y^(n)— are bonds, the formula R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m), is reduced to R^(o4)—CH═C(R^(o2))—(R^(o1)).

The polymerizable acid-containing unsaturated monomer which is the basis of one type of repeating units within the side chain of hybrid copolymer under another embodiment has the formula,

wherein T¹, T², and T³, are each independently H, a C₁ to C₃ alkyl group, carboxylic group, or a C₁ to C₃ alkyl carboxylic group, provided that acid-containing unsaturated monomer comprises two —COOH groups. The alkene compound has hydrogen, and three substituents, T¹, T², and T³, bound to the double bond. Group T¹ is trans to group T². Group T¹ is cis to group T³. Group T² is gem to group T³. The two —COOH groups can be bound directly to the alkene, or it can be bounded to the alkene via a small alkyl bridging group.

Under one embodiment of the present invention, the polymerizable acid-containing unsaturated monomer which is the basis for the side chains is an acid-containing acrylate monomer. The acid-containing acrylate monomer is of formula

CH₂═CH—CO—O—Y^(o)—R^(o1),

wherein

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

In cases where —Y^(o)— is a bond, —R^(o1) is H.

When the polymerizable acid-containing unsaturated monomer which is the basis for the side chains is an acid-containing acrylate monomer of formula CH₂═CH—CO—O—Y^(o)—R^(o1) then moiety —R^(o1) comprises the acid.

Examples of suitable polymerizable acid-containing acrylate include acrylic acid, 2-carboxyethyl acrylate, carboxylmethyl acrylate, 3-carboxylpropyl acrylate, 4-carboxybutyl acrylate, sulfomethyl acrylate, 2-sulfoethyl acrylate, 3-sulfopropyl acrylate, 4-sulfobutyl acrylate, ethylene glycol acrylate phosphate, propylene glycol acrylate phosphate, and butylene glycol acrylate phosphate.

Under another embodiment of the present invention, the polymerizable acid-containing unsaturated monomer that is the basis for the side chains is an acid-containing methacrylate monomer. The acid-containing methacrylate monomer is of formula

CH₂═C(CH₃)—CO—O—Y^(o)—(R^(o1))_(m),

wherein

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

In cases where —Y^(o)— is a bond, —R^(o1) is H.

Examples of suitable polymerizable acid-containing methacrylate include methacrylic acid, carboxylmethyl methacrylate, 3-carboxylpropyl methacrylate, 4-carboxybutyl methacrylate, 2-carboxyethyl methacrylate, sulfomethyl methacrylate, 2-sulfoethyl methacrylate, 3-sulfopropyl methacrylate, 4-sulfobutyl methacrylate, ethylene glycol methacrylate phosphate, propylene glycol methacrylate phosphate, and butylene glycol methacrylate phosphate.

The acid-containing vinyl monomer has the formula

CH₂═CH—Y^(o)—(R^(o1))_(m),

wherein

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups;

—R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

Examples of suitable acid-containing vinyl monomer include 4-vinylbenzoic acid, 4-styrenesulfonic acid, 1-vinyl-1H-pyrrole-2-carboxylic acid, 4-ethyl-5-phenyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-(4-methoxyphenyl)-1-vinyl-1H-pyrrole-2-carboxylic acid, 5-p-tolyl-1-vinyl-1H-pyrrole-2-carboxylic acid, 2-vinyl-1,1-cyclopropanedicarboxylic acid, and vinyl sulfonic acid.

The acid-containing alkylallyl monomer has the formula

CH₂═C(R^(o2))—Y^(o)—R^(o1),

wherein

—R^(o2) is C₁ to C₃ alkyl group;

—Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups;

—R^(o1) is —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding.

An example of suitable acid-containing alkylallyl monomer is methylallyl sulfonic acid.

The monocarboxylic acid-containing alkene which is the basis of one type of repeating units within the side chain of hybrid copolymer under one embodiment has the formula

R^(o4)—CH═C(R^(o2))—CO—OH,

wherein

R^(o4)— is C₁ to C₃ alkyl group, or an aryl group; and

—R² is H or C₁ to C₃ alkyl group.

C₁ to C₃ alkyl group is a methyl group, ethyl group, n-propyl group, or an i-propyl group.

The performance characteristics of the hybridized copolymer of the present invention is in large part determined by the chemical and physical characteristics of the hydrophobic functional polymeric backbone and of the copolymeric side chains attached to the backbone, as well as the ratios of the polymeric units comprising the hybridized copolymer. There are several factors that appear to be important in order to obtain an ink that would have the desirable characteristics, including the following: (1) the molar ratio of polymerizable acid-containing unsaturated monomer to the functionality of the functionalized hydrophobic polymer; (2) the molar ratio of polymerizable unsaturated monomer to the polymerizable acid-containing unsaturated monomer; and (3) the molar ratio of the polymerizable acid-containing unsaturated monomer in the first monomer component to the polymerizable acid-containing unsaturated monomer in the second monomer component.

The molar ratio of polymerizable acid-containing unsaturated monomer to the functionality of the functionalized hydrophobic polymer, is the ratio of the total number of moles of the acid-containing unsaturated monomer that is added to the reaction mixture in both monomer components, to the number of moles of functionality on the functionalized hydrophobic polymer. The number of moles of the functionality is the number of moles of the functionalized hydrophobic polymer multiplied by the functionality of the functionalized hydrophobic polymer. Many different ratios may yield acceptable results, however, based on the data presented herein, it is expected that the hybridized copolymer exhibits improved properties when the molar ratio of polymerizable acid-containing unsaturated monomer to the functionality of the functionalized hydrophobic polymer is between 3:1 and 12:1.

The molar ratio of the polymerizable unsaturated monomer to the polymerizable acid-containing unsaturated monomer, is the ratio of the total number of moles of the polymerizable unsaturated monomer that is added to the reaction mixture in both monomer components, to the total number of moles the polymerizable acid-containing unsaturated monomer that is added to the reaction mixture in both monomer components. For these calculations the number of moles of polymerizable unsaturated monomer from all sources are added together, and compared to the number of moles of polymerizable acid-containing unsaturated monomer added together from all sources. Various ratios may yield acceptable results, however, the hybridized copolymer is expected exhibits improved properties when the molar ratio of the polymerizable unsaturated monomer to the polymerizable acid-containing unsaturated monomer is between 20:1 and 5:1.

The molar ratio of the polymerizable acid-containing unsaturated monomer in the first monomer component to the polymerizable acid-containing unsaturated monomer in the second monomer component, is the ratio of the number of moles of the polymerizable acid-containing unsaturated monomer that is added to the reaction mixture in the first monomer components, to the number of moles the polymerizable acid-containing unsaturated monomer that is added to the reaction mixture in the second monomer components. Various ratios may yield acceptable results, however, the hybridized copolymer is expected to exhibit improved properties when the molar ratio of the polymerizable acid-containing unsaturated monomer in the first monomer component to the polymerizable acid-containing unsaturated monomer in the second monomer component is between 1:1 and 1:3.

The copolymeric side chains that are attached to the hydrophobic functional polymeric backbone may optionally comprise additional components. Such components may be added within the structure of side chains, and may be used to improve the physical or chemical properties of the hybridized copolymer, such as the stability of the ink. One such component is a structural unit that acts as a UV absorber. Such a UV absorber will dissipate the energy that is absorbed by the printed ink thus mitigating the aging process of the printed ink. Examples of UV absorbers that may be incorporated into the side chains are described above.

Another aspect of the present invention is the method for preparing the hybridized copolymer by a two-part synthesis process.

In the two-part synthesis process for preparing the hybridized copolymer, the process comprises the steps of

(a) reacting a functionalized hydrophobic polymer of an average molecular mass from about 15 to about 200 kilodaltons, with a hybridizing compound to create a reaction mixture;

(b) adding a monomer component to the reaction mixture; and

(c) neutralizing the reaction mixture with a base;

wherein the hydrophobic polymer is selected from the group consisting of a polysiloxane polymer, a polyolefin polymer, and a polyvinyl polymer or a copolymer thereof; and

wherein the monomer component comprises a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer.

This preparation for the hybridized copolymer may add one or more additional steps before steps (a), (b), and (c). The preparation for the hybridized copolymer may add one or more additional steps after steps (a), (b), and (c). The preparation for the hybridized copolymer may add one or more additional steps between any of the steps (a), (b), and (c). Such additional steps may include adding further reactants, adding a third or fourth or additional monomer components to the reaction mixture, changing the reaction conditions, working up the reaction mixture, and purifying any of reactants.

Further, any of the individual steps (a), (b), and (c) may comprise additional necessary components or sub-steps in order to prepare the hybridized copolymer. For example, in addition to the two components mentioned in step (a), namely the functionalized hydrophobic polymer and the hybridizing compound, this step typically also requires additional components such as a solvent and a catalyst.

In step (a) of the two-part synthesis of the hybridized copolymer, the functionalized hydrophobic polymer is reacted with the hybridizing compound. This step is similar to step (a) of the three-part synthesis of the hybridized copolymer. The definition of the functionalized hydrophobic polymer used in the two-part synthesis is the same as for the three-part synthesis. The definition of the hybridizing compound used in the two-part synthesis is the same as for the three-part synthesis. The definition of molar ratios of the components used in the two-part synthesis is the same as for the three-part synthesis. The definition of optional additives for inclusion in part (a) is the same as for the three-part synthesis.

Although the definitions of the functionalized hydrophobic polymer, hybridizing compound, molar ratios, and optional additives for step (a) in the two part synthesis is the same in step (a) in the three part synthesis, the functionalized hydrophobic polymer, hybridizing compound, molar ratios, and optional additives used in step (a) in the two part synthesis are not the same as in step (a) of the three part synthesis. For example, in order to achieve a working solution the loading level of the polymerization initiator may be higher than in the corresponding three part synthesis, because there is no step in the two part synthesis which would correspond to an intermediate step between step (b) and step (c) of the three part synthesis.

The reaction of the functionalized hydrophobic polymer with a hybridizing compound yields a reaction mixture which can then be reacted further. Step (b) follows step (a), either immediately, or after some intermediate steps that follow step (a) and precede step (b).

In step (b), the monomer component is added to the reaction mixture. Upon addition of the monomer component, the monomers comprising the monomer component react with the reaction product of functionalized hydrophobic polymer and hybridizing compound, to create a pre-neutralized hybrid copolymer. The monomer component upon exposure to the reaction mixture polymerizes with the alkene groups on the functionalized hydrophobic polymer that has been reacted with the hybridizing compound, wherein the alkene corresponds to the first functional group on the hybridizing compound.

The molar ratio of the monomers of the monomer component to the alkene groups on the functionalized hydrophobic polymer determines the length of the copolymeric side chains on the hybridized copolymer. For example, for a molar ratio of 10:1, the average length of the side chain on the hybridized copolymer will be 10 units.

The monomer component comprises at least one polymerizable unsaturated monomer and at least one polymerizable acid-containing unsaturated monomer. The monomer component may comprise the polymerizable unsaturated monomer and the polymerizable acid-containing unsaturated monomer. The monomer component may comprise a plurality of polymerizable unsaturated monomers and the polymerizable acid-containing unsaturated monomers. The monomer component may comprise the polymerizable unsaturated monomer and a plurality of polymerizable acid-containing unsaturated monomers. The monomer may comprise a plurality of polymerizable unsaturated monomers and a plurality of polymerizable acid-containing unsaturated monomers.

The definitions of the polymerizable unsaturated monomer and the polymerizable acid-containing unsaturated monomer for the two-part synthesis are the same as for the three-part synthesis, as presented above.

Additionally, the monomer component may comprise an additional additive. Examples of such an additive include a solvent, a diluent, a catalyst, an initiator, a hybridizing compound, and a UV absorber. The definition of possible solvents, catalysts, initiators, hybridizing compounds, and UV absorbers is the same as for step (b) or step (c) in the three-part synthesis.

The reaction of the monomer component with the reaction product of the functionalized hydrophobic polymer and hybridizing compound results in the pre-neutralized hybrid copolymer. In step (c), the pre-neutralized hybrid copolymer is neutralized with a base.

The neutralization of the pre-neutralized hybrid copolymer completes the formation of the hybrid copolymer. The hybrid copolymer may then be precipitated, or washed, or isolated, or further used in the preparation of a liquid ink.

The base that is used to neutralize the pre-neutralized hybrid copolymer is strong enough to cause neutralization to occur, but is not strong enough to degrade the pre-neutralized hybrid copolymer. The base is preferably a weak base. Examples of suitable bases include secondary amines and tertiary amines. The secondary amine is a compound comprising the group R—NH—R, wherein moieties R are each aliphatic groups which may or may not be the same. The tertiary amine is a compound comprising the group R₃N, wherein moieties R are aliphatic groups which may or may not be the same as the other groups.

An example of a suitable weak base is dimethylethanolamine. In one embodiment the acid is a mixture of two or more acids.

Following step (c) of the synthesis of the hybridized copolymer of the present invention by the two-part synthesis, additional steps may be needed to obtain the hybridized copolymer. Such steps may include an addition of a solvent, a diluent, a polymerization initiator, a catalyst, or any mixture thereof. Such steps may also include partial evaporation of the solvent.

Another aspect of the present invention is the method for preparing the hybridized copolymer by a one-part synthesis process.

In the one part synthesis process for preparing the hybridized copolymer, the process comprises the steps of

(a) mixing a functionalized hydrophobic polymer of an average molecular mass from about 15 to about 200 kilodaltons, a hybridizing compound, a polymerizable unsaturated monomer, and a polymerizable acid-containing unsaturated monomer to create a reaction mixture;

(b) delivering energy to the reaction mixture to cause a polymerization reaction to occur within the reaction mixture; and

(c) neutralizing the reaction mixture with a base;

wherein the hydrophobic polymer is selected from the group consisting of a polysiloxane polymer, a polyolefin polymer, and a polyvinyl polymer, or a copolymer thereof.

This preparation for the hybridized copolymer may add one or more additional steps before steps (a), (b), and (c). The preparation for the hybridized copolymer may add one or more additional steps after steps (a), (b), and (c). The preparation for the hybridized copolymer may add one or more additional steps between any of the steps (a), (b), and (c). Such additional steps may include adding further reactants, adding additional monomer components to the reaction mixture, changing the reaction conditions, working up the reaction mixture, and purifying any of reactants.

Further, any of the individual steps (a), (b), and (c) may comprise additional necessary components or sub-steps in order to prepare the hybridized copolymer. For example, in addition to the four components mentioned in step (a), namely the functionalized hydrophobic polymer, the hybridizing compound, the polymerizable unsaturated monomer, and the polymerizable acid-containing unsaturated monomer, this step typically also requires additional components such as a solvent and a catalyst.

In step (a) of the one part synthesis of the hybridized copolymer, the functionalized hydrophobic polymer is mixed with the hybridizing compound, as well as with the polymerizable unsaturated monomer, and the polymerizable acid-containing unsaturated monomer. The definition of the functionalized hydrophobic polymer used in the one part synthesis is the same as for the three-part synthesis. The definition of the hybridizing compound used in the one part synthesis is the same as for the three-part synthesis. The molar ratios of the components used in the one part synthesis is the same as for the three-part synthesis. The definition of the polymerizable unsaturated monomer in the one part synthesis is the same as for the three-part synthesis. The definition of the polymerizable acid-containing unsaturated monomer in the one part synthesis is the same as for the three-part synthesis. The definition of optional additives for inclusion in part (a) is the same as for additives in parts (a), (b), and (c) in the three part synthesis.

Although the molar ratios, and the definitions of the functionalized hydrophobic polymer, hybridizing compound, polymerizable unsaturated monomer, polymerizable acid-containing unsaturated monomer and optional additives for step (a) in the one part synthesis is the same as in steps (a), (b) and (c) in the three part synthesis, the molar ratios, functionalized hydrophobic polymer, hybridizing compound, polymerizable unsaturated monomer, polymerizable acid-containing unsaturated monomer, and optional additives used in step (a) in the one part synthesis may not necessarily be the same as in steps (a), (b) and (c) of the three part synthesis. For example, in order to achieve a working solution the loading level of the polymerization initiator may be higher than in the corresponding three part synthesis, because there is no step in the two part synthesis which would correspond to an intermediate step between step (b) and step (c) of the three part synthesis.

In order for the functionalized hydrophobic polymer, the hybridizing compound to react, and further, in order for the polymerizable unsaturated monomer, and polymerizable acid-containing unsaturated monomer to polymerize with the reaction product of the functionalized hydrophobic polymer and the hybridizing compound, a sufficient energy must be delivered to the reaction mixture in order to traverse the activation energies of reactions. The energy may be delivered by heating, radiation, shear mixing, or sonication.

Alternatively, the activation energies of the various reactions may be lowered by a serial addition of appropriate initiators and catalysts. For example, the mixture of the functionalized hydrophobic polymer, the hybridizing compound, the polymerizable unsaturated monomer, and polymerizable acid-containing unsaturated monomer, and optionally any additives, may be exposed to a catalyst, followed by an addition of an initiator. The catalyst may cause the functionalized hydrophobic polymer to react with the hybridizing compound; the later addition of an initiator may cause the polymerization of the monomers with the reaction product of the functionalized hydrophobic polymer and the hybridizing compound.

Under another embodiment the reaction of the functionalized hydrophobic polymer with the hybridizing compound may be caused by a low to moderate heating of the reaction mixture, followed by moderate to high heating of the reaction mixture to cause polymerization of the polymerizable unsaturated monomers, and polymerizable acid-containing unsaturated monomers with the backbone.

Under another embodiment the reaction of the functionalized hydrophobic polymer with the hybridizing compound may be caused by a low to moderate heating of the reaction mixture, followed by an addition of an initiator to cause polymerization of the polymerizable unsaturated monomers, and polymerizable acid-containing unsaturated monomers with the backbone.

Under another embodiment the reaction of the functionalized hydrophobic polymer with the hybridizing compound may be caused by an addition of a catalyst to the reaction mixture, followed by an addition of an initiator to cause polymerization of the polymerizable unsaturated monomers, and polymerizable acid-containing unsaturated monomers with the backbone.

Under another embodiment the reaction of the functionalized hydrophobic polymer with the hybridizing compound may be caused by an addition of a catalyst to the reaction mixture, followed by heating of the reaction mixture to cause polymerization of the polymerizable unsaturated monomers, and polymerizable acid-containing unsaturated monomers with the backbone.

Although administering energy to the reaction mixture is needed in order to overcome the activation barrier, it is necessary to manage the temperature of the reaction mixture. Because the polymerization reaction is generally an exothermic process, the management of the temperature of the reaction mixture includes cooling of the reaction mixture. The cooling helps in obviating evaporation of the solvent, and in advancing the reaction.

The reaction of the polymerizable unsaturated monomer and the polymerizable acid-containing unsaturated monomer with the reaction product of the functionalized hydrophobic polymer and hybridizing compound results in the pre-neutralized hybrid copolymer. In step (c) of the one part synthesis, the pre-neutralized hybrid copolymer is neutralized with a base.

The neutralization of the pre-neutralized hybrid copolymer completes the formation of the hybrid copolymer. The hybrid copolymer may then be precipitated, or washed, or isolated, or further used in the preparation of the liquid ink.

The base that is used to neutralize the pre-neutralized hybrid copolymer in step (c) of the one part synthesis is strong enough to cause neutralization to occur, but it is not be strong enough to degrade the pre-neutralized hybrid copolymer. The base is preferably a weak base. Examples of suitable bases include secondary amines and tertiary amines. The secondary amine is a compound comprising the group R—NH—R, wherein moieties R are each aliphatic groups which may or may not be the same. The tertiary amine is a compound comprising the group R₃N, wherein moieties R are aliphatic groups which may or may not be the same as the other groups.

An example of a suitable weak base includes dimethylethanolamine. In one embodiment the base is a mixture of two or more bases.

Following step (c) of the synthesis of the hybridized copolymer of the present invention by the two-part synthesis, additional steps may be needed to obtain the hybridized copolymer. Such steps may include an addition of a solvent, a diluent, a polymerization initiator, a catalyst, or any mixture thereof. Such steps may also include partial evaporation of the solvent.

Experimental

The following example that illustrates several aspects of the present invention. The preparative and analytical techniques were undertaken using common laboratory techniques or techniques which have been adapted to suit the purpose.

A mixture of 80.0 g of toluene, 75.0 g of methyl ethyl ketone, 70.0 g of Eastman™ Adhesion Promoter AP 550-1 (a non-chlorinated adhesion promoter available from Eastman Chemical Company), 4.0 g of allyl glycidyl ether, and 2.0 g of Silmer NH-Di-50 (a linear silicone with reactive amine terminal groups with primary amine value of 20 to 35, CAS No. 106214-84-0, available from Siltech Corporation) was charged into a 3 liter 4-neck round bottom flask equipped with a grade 316 stainless steel stirrer, thermocouple, and temperature controller, heating mantle, two metering addition funnels, nitrogen supply line, and reflux condenser. The resulting reaction mixture in the flask was stirred under nitrogen for one hour. After an addition of 33.0 g of UCAR™ VMCC (a vinyl terpolymer comprising 83 wt % vinyl chloride and 16 wt % vinyl acetate, and 1 wt % maleic acid, mw 19 kDa, available from Dow Chemical Company) to the reaction mixture, the temperature of the flask was raised to 80° C.

In a separate flask, an initiator component was prepared by dissolving 4.0 g of 2,2′-azodi(isobutyronitrile) (available as Perkadox® AMBN-gr from Akzo Nobel Polymer Chemicals LLC) in 50.0 g of methyl ethyl ketone. A monomer component, consisting of 5.0 g of hydroxyethyl acrylate, 15.0 g of methacrylic acid, 20.0 g of isobornyl methacrylate, 30.0 g of methyl 2-methylacrylate, and 0.5 g of Ruva 93 (2-[3-(2H-Benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate, CAS No. 96478-09-0, available from Otsuka Chemical Co., Ltd.), was added simultaneously with the initiator component to the reaction flask over a period of 60 minutes.

After one hour hold time, the reaction mixture was sampled to check for conversion. 6.0 g of N,N-dimethylethanolamine dissolved in 300.0 g of water was added over 30 minutes. A dean stark trap attached to the reaction flask setup, the temperature was raised to 95° C., and about 210 g of the solvent was distilled from the reaction mixture to yield a milky white to opalescent liquid. The formed polymer was found to contain 29.5% solids, had a viscosity of ˜600 centipoises, and pH of 8.2.

The testing for solids was performed by the following procedure. Approximately 300 mg sample of the material to be tested is weighed and spread evenly on an aluminum weighing boat with an optional aid of a solvent. The sample is air dried in about 10 minutes, placed into a 150° C. oven for 30 minutes, cooled to room temperature, and weighed. The percent solid of the material is the ratio of the dried sample weight to the initial sample weight. Completeness of evaporation of the solvents is assured by placing the dried sample into the oven for additional 30 minutes, cooling and reweighing. The material was tested in triplicate.

The formed polymer exhibited good adhesion to a vinyl substrate.

While it is apparent that the embodiment of the invention herein disclosed are well suited to fulfill the objectives stated above, it will be appreciated that numerous modifications and embodiments may be implemented by those skilled in the art, and it is intended that the appended claims cover all such modification and embodiments that fall within the true spirit and scope of the present invention.

A number of references have been cited and the entire disclosures of which are incorporated herein by reference. 

1. A hybridized copolymer comprising: (a) a hydrophobic functional polymeric backbone of an average molecular mass from about 15 to about 200 kilodaltons, wherein the functional polymeric backbone comprises a polymer selected from the group consisting of a functional polysiloxane polymer, a functional polyolefin polymer, and a functional polyvinyl polymer; and (b) a plurality of copolymeric side chains attached to the backbone, wherein one or more side chains comprises a reaction product of at least a polymerizable unsaturated monomer and a polymerizable acid-containing unsaturated monomer.
 2. The hybridized copolymer of claim 1, wherein the polymeric backbone is a copolymer of (i) a functional polyvinyl polymer; and (ii) a functional polysiloxane polymer, or a functional polyolefin polymer, or both.
 3. The hybridized copolymer of claim 2, wherein the polymeric backbone comprises 10 to 60 weight percent of the functional polyvinyl polymer.
 4. The hybridized copolymer of claim 1, wherein the polymerizable unsaturated monomer is selected from a group consisting of an acrylate monomer, an alkacrylate monomer, an aromatic vinyl monomer, an aliphatic vinyl monomer, a vinyl ester monomer, a vinyl cyanogen-containing monomer, a halogenoid monomer, an olefin monomer, and a diene monomer.
 5. The hybridized copolymer of claim 1, wherein the polymerizable unsaturated monomer has the formula CH₂═C(R²)—X—Y—R¹, wherein —R² is H, halogen, or C₁ to C₃ alkyl group; —X— is a bond, —CO—O—, or —O—CO—; —Y— is a bond, or a C₁ to C₂₂ bridging alkyl group optionally substituted with one or more C₁ to C₆ alkyl groups; and —R¹ is (1) H, halogen, —OH, or —CN; (2) a C₃ to C₈ cycloalkyl group that is optionally substituted with one or more linear or branched C₁ to C₆ alkyl group; (3) a C₃ to C₈ heterocycloalkyl group comprising one or more heteroatoms, wherein the heteroatom is a chalcogen; (4) a C₇ to C₁₅ bicycloalkyl group that is optionally substituted with one or more halogens, or linear or branched C₁ to C₆ alkanes; (5) a C₆ to C₁₄ aryl group that is optionally substituted with one or more groups selected from the group consisting of a halogen, a linear or branched C₁ to C₆ alkane, and C₁ to C₃ alkyloxy; (6) SiR³ ₃, wherein R³ is C₁ to C₃ alkyl group; (7) polyethylene glycol, polypropylene glycol, or a copolymer thereof, terminated with —OH or —OMe; or (8) —CZ═CH₂, wherein Z is H or halogen.
 6. The hybridized copolymer of claim 1, wherein the polymerizable acid-containing unsaturated monomer is selected from the group consisting of an acid-containing acrylate, an acid-containing methacrylate, an acid-containing vinyl monomer, an acid-containing alkylallyl monomer, a monocarboxylic acid-containing alkene, a dicarboxylic acid-containing alkene, a salt of any of the preceding, and an ester of any of the preceding.
 7. The hybridized copolymer of claim 1, wherein the polymerizable acid-containing unsaturated monomer has the formula R^(o4)—CH═C(R^(o2))—X^(o)—Y^(o)—(R^(o1))_(m), wherein R^(o4)— is H, C₁ to C₃ alkyl group, or an aryl group; —R^(o2) is H, halogen, or C₁ to C₃ alkyl group; —X^(o)— is a bond, or —CO—O—; —Y^(o)— is a bond, or a C₁ to C₁₈ bridging alkyl, cycloalkyl, or heterocycloalkyl group optionally substituted with one or more C₁ to C₆ alkyl groups, aryl groups or alkoxyaryl groups; —R^(o1) is H, —COOH, —SO₃H, or —OPO(OH)₂, or a salt of any of the preceding, and an ester of any of the preceding; and m=1 or
 2. 8. The hybridized copolymer of claim 1, wherein the polymerizable acid-containing unsaturated monomer has the formula

wherein T¹, T², and T³, are each independently H, a C₁ to C₃ alkyl group, carboxylic group, or a C₁ to C₃ alkyl carboxylic group, provided that acid-containing unsaturated monomer comprises two —COOH groups.
 9. An aqueous mixture of hybridized copolymer of claim
 1. 10. The aqueous mixture of claim 9, wherein the aqueous mixture comprises a colloidal dispersion suitable for use in preparation of a water based jet ink vehicle, wherein the particle size of more than 90% of particles in said dispersion is less than 500 nanometers.
 11. The aqueous mixture of claim 10, wherein the dispersion is prepared without the use of a surfactant.
 12. The aqueous mixture of claim 9, wherein the mixture further comprises an antimicrobial.
 13. A liquid ink comprising more than 50 weight percent of water, the hybridized copolymer of claim 1, and a pigment or a dye.
 14. A process for preparing a hybridized copolymer comprising the steps of (a) reacting a functionalized hydrophobic polymer of an average molecular mass from about 15 to about 200 kilodaltons, with a hybridizing compound to create a reaction mixture; (b) adding a first monomer component to the reaction mixture; (c) adding a second monomer component to the reaction mixture; and (d) neutralizing the reaction mixture with a base; wherein the hydrophobic polymer is selected from the group consisting of a polysiloxane polymer, a polyolefin polymer, a polyvinyl polymer, and a copolymer thereof; wherein the first monomer component, or the second monomer component, or both monomer components comprise a polymerizable unsaturated monomer; and wherein the first monomer component, or the second monomer component, or both monomer components comprise a polymerizable acid-containing unsaturated monomer.
 15. The process of claim 14, wherein the hydrophobic polymer comprises a copolymer of vinyl chloride, vinyl acetate, and maleic anhydride.
 16. The process of claim 14, wherein the first monomer component comprises the polymerizable unsaturated monomer, wherein the polymerizable unsaturated monomer is selected from the group consisting of an acrylate monomer, a methacrylate monomer, an aromatic vinyl monomer, a vinyl ester monomer, a vinyl cyanogen-containing monomer, a halogenoid monomer, an olefin monomer, and a diene monomer.
 17. The process of claim 14, wherein the first monomer component comprises the polymerizable acid-containing unsaturated monomer which is selected from the group consisting of an acid-containing acrylate, an acid-containing methacrylate, an acid-containing vinyl monomer, an acid-containing alkylallyl monomer, a monocarboxylic acid-containing alkene, a dicarboxylic acid-containing alkene, a salt of any of the preceding, and an ester of any of the preceding.
 18. The process of claim 14, wherein the molar ratio of the polymerizable unsaturated monomer to the polymerizable acid-containing unsaturated monomer is from 20:1 to 5:1.
 19. The process of claim 14, wherein the second monomer component comprises the polymerizable unsaturated monomer, wherein the polymerizable unsaturated monomer is selected from the group consisting of an acrylate monomer, a methacrylate monomer, an aromatic vinyl monomer, a vinyl ester monomer, a vinyl cyanogen-containing monomer, a halogenoid monomer, an olefin monomer, and a diene monomer.
 20. The process of claim 14, wherein the second monomer component comprises polymerizable acid-containing unsaturated monomer, wherein the polymerizable acid-containing unsaturated monomer is selected from the group consisting of an acid-containing acrylate, an acid-containing methacrylate, an acid-containing vinyl monomer, an acid-containing alkylallyl monomer, a monocarboxylic acid-containing alkene, a dicarboxylic acid-containing alkene, a salt of any of the preceding, and an ester of any of the preceding. 